[chore] Release notes for v0.149.0

[akhileshsingh85]

Description: prepare for Changelog v0.149.0

• Remove unrelated changes from the Changelog.md file

🛑 Breaking changes 🛑

• (Contrib) exporter/elasticsearch: Remove host.os.type encoding in ECS mode (#46900)
  Use processor/elasticapmprocessor v0.36.2 or later for host.os.type enrichment

🚩 Deprecations 🚩

• (Contrib) receiver/awsfirehose: Deprecate built-in unmarshalers (cwlogs, cwmetrics, otlp_v1) in favor of encoding extensions. (#45830)
  Use the aws_logs_encoding extension (format: cloudwatch) instead of cwlogs,
  and the awscloudwatchmetricstreams_encoding extension instead of cwmetrics (format: json)
  or otlp_v1 (format: opentelemetry1.0).

💡 Enhancements 💡

• (Contrib) cmd/opampsupervisor: Add configuration validation before applying remote config to prevent collector downtime (#41068)
  Validates collector configurations before applying them, preventing downtime from invalid remote configs.
  Disabled by default. Enable via agent.validate_config: true. May produce false positives when resources
  like ports are temporarily unavailable during validation.
• (Contrib) connector/datadog: Document datadog connector is not supported in aix environments (#47010)
  Explicitly opt out of host metadata computation in datadog components to support AIX compilation target.
• (Contrib) connector/signal_to_metrics: Add keys_expression support in include_resource_attributes and attributes for dynamic attribute key resolution at runtime (#46884)
  The keys_expression field allows specifying an OTTL value expression that resolves to a list
  of attribute keys at runtime. This enables dynamic resource attribute filtering based on runtime
  data such as client metadata. Exactly one of key or keys_expression must be set per entry.
• (Contrib) connector/signal_to_metrics: Reduce per-signal allocations in the hot path by replacing attribute map allocation with a pooled hash-based ID check, and caching filtered resource attributes per metric definition within each resource batch. (#47197)
• (Contrib) connector/signal_to_metrics: Pre-compute prefixed collector key to avoid a string allocation on every signal processed. (#47183)
  Pre-computing the collector key avoids a string allocation on every signal processed.
• (Contrib) exporter/datadog: Document datadog exporter is not supported in aix environments (#47010)
  Explicitly opt out of host metadata computation in datadog components to support AIX compilation target.
• (Contrib) exporter/elasticsearch: Add histogram:raw mapping hint to bypass midpoint approximation for histogram metrics (#47150)
• (Contrib) exporter/elasticsearch: Cache metric attribute set per bulk session instead of recomputing it for every document (#47170)
  syncBulkIndexerSession.Add() was calling getAttributesFromMetadataKeys +
  attribute.NewSet + metric.WithAttributeSet on every document in the hot path. The attribute set is
  derived from the request context metadata, which is constant for the lifetime of a session, so it is
  now computed once in StartSession and reused across all Add() calls in that session.
• (Contrib) exporter/elasticsearch: populate _doc_count field in ECS mapping mode (#46936)
  _doc_count is a special metadata field in Elasticsearch used when a document represents pre-aggregated data (like histograms or aggregate metrics).
  Currently, elasticsearchexporter only populates this field for otel mapping mode (native otel field structure). This change
  adds support for ECS mapping mode (native ECS field structure) so that we have consistent behavior for both mapping modes.
• (Contrib) exporter/elasticsearch: Encode require_data_stream in Elasticsearch bulk action metadata instead of the bulk request query string. (#46970)
  This preserves existing endpoint query parameters while moving require_data_stream
  to the per-document action line expected by newer bulk workflows. Benchmarks show
  a stable ~27 bytes/item NDJSON payload overhead before compression.
• (Contrib) exporter/elasticsearch: Improve performance of Elasticsearch exporter document serialisation (#47171)
• (Contrib) exporter/elasticsearch: Add metric for docs retried because of request errors (#46215)
• (Contrib) extension/datadog: Document datadog extension is not supported in aix environments (#47010)
  Explicitly opt out of host metadata computation in datadog components to support AIX compilation target.
• (Contrib) extension/db_storage: Make dbstorage work in AIX environments (#47010)
  sqlite support is offered via modernC, which doesn't support the AIX ppc64 compilation target.
  We carve out support for sqlite in AIX environments so contrib can compile for this compilation target.
• (Contrib) extension/health_check: Add component event attributes to serialized output. (#43606)
  When http.status.include_attributes is enabled in the healthcheckv2 extension (with use_v2: true),
  users will see additional attributes in the status output. These attributes provide more
  context about component states, including details like error messages and affected components.
  For example:

  {
    "healthy": false,
    "status": "error",
    "attributes": {
      "error_msg": "not enough permissions to read cpu data",
      "scrapers": ["cpu", "memory", "network"]
    }
  }

• (Contrib) extension/healthcheckv2: Add component event attributes to serialized output. (#43606)
  When http.status.include_attributes is enabled in the healthcheckv2 extension (with use_v2: true),
  users will see additional attributes in the status output. These attributes provide more
  context about component states, including details like error messages and affected components.
  For example:

  {
    "healthy": false,
    "status": "error",
    "attributes": {
      "error_msg": "not enough permissions to read cpu data",
      "scrapers": ["cpu", "memory", "network"]
    }
  }

• (Contrib) extension/sigv4auth: Add support for External IDs when assuming roles in cross-account authentication scenarios (#44930)
  Added external_id field to the AssumeRole configuration, allowing users to specify
  an External ID when assuming roles for enhanced cross-account security.
• (Contrib) internal/datadog: Do not compute host metadata in AIX environments (#47010)
  Explicitly opt out of host metadata computation in datadog components to support AIX compilation target.
• (Contrib) receiver/awslambda: Enrich context with AWS Lambda receiver metadata for S3 logs (#47046)
• (Contrib) receiver/expvar: Enable the re-aggregation feature for the expvar receiver (#45396)
• (Contrib) receiver/skywalking: Add feature gate translator.skywalking.useStableSemconv to update semantic conventions from v1.18.0 to v1.38.0 (#44796)
  A feature gate translator.skywalking.useStableSemconv has been added to control the migration.
  The gate is disabled by default (Alpha stage), so existing behavior is preserved.

🧰 Bug fixes 🧰

• (Contrib) processor/deltatorate: Append "/s" to the unit of output datapoints to reflect the per-second rate. (#46841)
• (Contrib) receiver/datadog: Propagate Datadog trace sampling priority to all spans translated from a trace chunk. (#45402)
• (Contrib) receiver/otelarrow: Remove assumed positions of otel arrow root payload types (#46878)
• (Contrib) receiver/otelarrow: Fix OTLP fallback handlers returning codes.Unknown instead of codes.Unavailable for pipeline errors, causing upstream exporters to permanently drop data instead of retrying. (#46182)
• (Contrib) receiver/pprof: Fixes pprofreceiver file_scrapper appending resource profiles instead of merging them. (#46991)

• Update CHANGELOG.md

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 26.04%. Comparing base (0afa316) to head (07e89bd).
⚠️ Report is 1 commits behind head on main.

❌ Your project status has failed because the head coverage (26.04%) is below the target coverage (35.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #7387   +/-   ##
=======================================
  Coverage   26.04%   26.04%           
=======================================
  Files         318      318           
  Lines       22926    22926           
=======================================
  Hits         5970     5970           
  Misses      16279    16279           
  Partials      677      677           

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[crobert-1]

A couple notes:

• Empty sections can be removed (ie New Components in this PR)
• Any changelog entries for components that are not in our distro can be removed. I usually use the components.go file for checking.

[akhileshsingh85]

@crobert-1 Thank you. I have updated the PR. Also included the removed content into the description.

[crobert-1]

Also, we should add the removed entry for extension/health_check since it's included in our distro.

[pjanotti]

I see that in the past let some mdatagen entries slip but I don't think those are necessary for us. Other than that LGTM, please add an entry for #7383 that I just merged 😬