…ventions detection

Move the RestoreEnableAnalyzerAssets opt-in gating into code, per target
framework. The value now flows through TargetFrameworkInformation and is read
by every restore entry point, including static-graph restore which previously
ignored the property entirely. Removes the project-level
ProjectRestoreMetadata.RestoreEnableAnalyzerAssets and the NuGet.targets OR.

Detect analyzers via a new AnalyzerAssemblies pattern in ManagedCodeConventions
instead of the hand-rolled IsAnalyzerAssetPath, so detection is shared with the
content model and matches the analyzers folder case-insensitively.

Clarify the analyzer metadata derivation comment and trim an allocation in the
compiler-version normalization.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Add five properties to the ProjectRestoreInformation event to size the impact
of enabling RestoreEnableAnalyzerAssets by default before the rollout:

- AnalyzerAssets.Excluded.Count
- AnalyzerAssets.PackagesWithAnalyzers.Count
- AnalyzerAssets.PackagesWithExcludedAnalyzers.Count
- AnalyzerAssets.ExcludedByPrivateAssets.Count
- AnalyzerAssets.ExcludedByExcludeAssets.Count

The counts are derived from the resolved dependency graphs and the package
file lists, so they are reported on every full restore regardless of whether
the feature is currently enabled. This lets us measure how many packages and
analyzer assemblies would stop being applied once PrivateAssets/ExcludeAssets
are honored. AnalyzerAssets.Count is redefined as the number of analyzer
assemblies that would apply (computed the same way), replacing the previous
count of analyzer assets written to the assets file.

Analyzer detection mirrors ManagedCodeConventions.ManagedCodePatterns.
AnalyzerAssemblies as a cheap string check, avoiding a content-item collection
allocation per package on the restore path.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Address spec review feedback (Client.Engineering#3855): the rollout decision is
driven by whether a package's analyzers are affected, not by how many individual
analyzer assemblies it ships.

- Remove AnalyzerAssets.Count (per-assembly applied count).
- Replace AnalyzerAssets.Excluded.Count with a binary AnalyzerAssets.Excluded
  (true when any package's analyzers would be filtered out for the project).

The package-level counts (PackagesWithAnalyzers.Count, PackagesWithExcludedAnalyzers.Count,
ExcludedByPrivateAssets.Count, ExcludedByExcludeAssets.Count) are unchanged. Per-package
detection now uses a HashSet rather than per-assembly counts.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Address PR feedback (#7464): use the NoAllocEnumerate helper for the IList
iterations in PopulateAnalyzerAssetsTelemetry.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Address PR feedback (#7464): look up TargetFrameworkInformation by (framework, alias)
via GetNearestTargetFramework instead of framework-only, in LockFileBuilder and the
analyzer-assets telemetry, so multi-targeted projects with aliased frameworks resolve
to the correct target framework.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Address PR feedback (#7464): treat RestoreEnableAnalyzerAssets as a project-wide
opt-in instead of per target framework. When any target framework opts in, analyzer
assets are honored for every target framework, mirroring how package pruning is
enabled project-wide once any framework qualifies (PackageSpecFactory.GetPackagePruningDefault).
The per-framework opt-in is already gated to .NET 11+ in NuGet.targets, so only a
qualifying framework can enable it.

Add a multi-targeted restore test asserting a non-opted-in framework still honors
analyzers when another framework opts in.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Address PR feedback (#7464): analyzer assets restore was force-disabled below
.NET 11 even when explicitly opted in. Mirror package pruning instead — default
to off, but honor an explicit RestoreEnableAnalyzerAssets opt-in (or opt-out) on
any target framework, so users can opt into the new behavior before it is enabled
by default. The net11 version gate only ever forced off the explicit opt-in; a
future default-on can gate itself the way RestorePackagePruningDefault does.

Update the availability tests: the opt-in is now honored on all frameworks, and
the value defaults to false when unset.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

RestoreEnableAnalyzerAssets was stored per target framework on
TargetFrameworkInformation, but analyzer assets are a project-wide opt-in.
Move it to ProjectRestoreMetadata (mirroring UsingMicrosoftNETSdk /
RestoreUseLegacyDependencyResolver / RestoreDoNotWriteDependencyGraphSpec) so
consumers read a single project-level value instead of scanning every
target framework.

- Model: add the property (plus Equals/GetHashCode/Clone) to
  ProjectRestoreMetadata and remove it from TargetFrameworkInformation.
- Serialization: read and write it under the "restore" metadata section.
- Readers: PackageSpecFactory, MSBuildStaticGraphRestore and
  MSBuildRestoreUtility now set it at the project level.
- LockFileBuilder and restore telemetry read the project-level value directly.
- NuGet.targets: emit RestoreEnableAnalyzerAssets on the ProjectSpec restore
  graph entry (not the per-framework entry) so the task-based restore path
  captures the opt-in; add a GenerateRestoreGraphFile functional test covering
  both the standard and static-graph evaluation paths.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Resolve target framework information by alias instead of selecting a nearest
framework. Keep warning and dependency alias handling safe when no exact
framework metadata exists.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c1c3025b-91e0-4a52-9c20-8162710176f6

Exercise LockFileBuilder with a target graph alias that is absent from the
PackageSpec so exact alias lookup remains null-safe.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c1c3025b-91e0-4a52-9c20-8162710176f6

Preserve project-wide analyzer behavior after moving the setting to restore
metadata. Promote an enabled outer or inner build consistently across standard,
PackageSpecFactory, and static graph restore paths.

Add focused unit coverage and an SDK-next NET10/NET11 restore matrix that verifies
analyzers are written for every target framework.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c1c3025b-91e0-4a52-9c20-8162710176f6

Run the multi-target analyzer assets test on the default SDK 11 test target and align its name with the project-wide opt-in scenario.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Copilot-Session: dc2642ca-597e-4ac9-b965-80b0fbd3b338