fix(skills): hash bytes bundle contents

[helix4u]

Summary

Fixes the skills hub update/check crash when fetched skill bundle file contents are bytes instead of strings.

SkillBundle.files is typed to allow str | bytes, and some source adapters intentionally populate bytes for bundled assets. bundle_content_hash() only handled strings, so update checks could crash with AttributeError: bytes object has no attribute encode.

Changes

• Hash bytes bundle contents directly.
• Continue encoding string bundle contents as UTF-8.
• Add a regression test for bytes-backed bundle files.

Validation

• PASS: scripts/run_tests.sh tests/tools/test_skills_hub.py::TestCheckForSkillUpdates::test_bundle_content_hash_accepts_bytes_file_content tests/tools/test_skills_hub.py::TestCheckForSkillUpdates::test_bundle_content_hash_matches_installed_content_hash
• PASS: scripts/run_tests.sh tests/tools/test_skills_hub.py — 104 passed
• FAIL: scripts/run_tests.sh — 31 failed, 19090 passed, 51 skipped, 222 warnings in 503.36s. The failures are outside this PR surface; no failures were in tests/tools/test_skills_hub.py.

Full-suite failing tests observed:

• tests/acp/test_server.py::TestSessionOps::test_send_available_commands_update
• tests/cli/test_cli_secret_capture.py::test_secret_capture_callback_can_be_completed_from_cli_state_machine
• tests/gateway/test_approve_deny_commands.py::TestBlockingApprovalE2E::test_blocking_approval_approve_once
• tests/gateway/test_approve_deny_commands.py::TestBlockingApprovalE2E::test_blocking_approval_deny
• tests/gateway/test_config.py::TestLoadGatewayConfig::test_bridges_quoted_false_platform_enabled_from_config_yaml
• tests/agent/test_auxiliary_client.py::TestGetTextAuxiliaryClient::test_custom_endpoint_uses_codex_wrapper_when_runtime_requests_responses_api
• tests/gateway/test_dingtalk.py::TestCardLifecycle::test_final_reply_finalizes_card
• tests/gateway/test_dingtalk.py::TestCardLifecycle::test_intermediate_send_stays_streaming
• tests/gateway/test_dingtalk.py::TestCardLifecycle::test_done_fires_only_when_reply_to_is_set
• tests/gateway/test_dingtalk.py::TestCardLifecycle::test_edit_message_finalize_fires_done
• tests/gateway/test_dingtalk.py::TestCardLifecycle::test_edit_message_finalize_false_tracks_sibling
• tests/gateway/test_dingtalk.py::TestCardLifecycle::test_next_send_auto_closes_sibling_streaming_cards
• tests/gateway/test_dingtalk.py::TestDingTalkAdapterAICards::test_send_uses_ai_card_if_configured
• tests/gateway/test_discord_bot_filter.py::TestDiscordBotFilter::test_default_is_none
• tests/gateway/test_teams.py::TestTeamsSend::test_send_typing
• tests/gateway/test_api_server.py::TestAdapterInit::test_default_config
• tests/hermes_cli/test_backup.py::TestProfileRestoration::test_import_creates_profile_wrappers
• tests/hermes_cli/test_cmd_update.py::TestCmdUpdateBranchFallback::test_update_refreshes_repo_and_tui_node_dependencies
• tests/hermes_cli/test_update_gateway_restart.py::TestCmdUpdateLaunchdRestart::test_update_restarts_profile_manual_gateways
• tests/hermes_cli/test_update_gateway_restart.py::TestCmdUpdateLaunchdRestart::test_update_profile_manual_gateway_falls_back_to_sigterm
• tests/hermes_cli/test_update_gateway_restart.py::TestServicePidExclusion::test_update_kills_manual_pid_but_not_service_pid
• tests/plugins/test_kanban_dashboard_plugin.py::test_ws_events_rejects_when_token_required
• tests/run_agent/test_concurrent_interrupt.py::test_concurrent_interrupt_cancels_pending
• tests/run_agent/test_concurrent_interrupt.py::test_running_concurrent_worker_sees_is_interrupted
• tests/test_tui_gateway_server.py::test_session_create_drops_pending_title_on_valueerror
• tests/tools/test_dockerfile_pid1_reaping.py::test_dockerfile_installs_tui_dependencies
• tests/tools/test_dockerfile_pid1_reaping.py::test_dockerfile_materializes_local_tui_ink_package
• tests/tools/test_credential_pool_env_fallback.py::TestCredentialPoolSeedsFromDotEnv::test_os_environ_still_wins_over_dotenv
• tests/tools/test_approval_plugin_hooks.py::TestGatewayPathFiresHooks::test_pre_and_post_fire_on_gateway_surface
• tests/tools/test_mcp_tool.py::TestSamplingErrors::test_timeout_error
• tests/tools/test_tirith_security.py::TestDiskFailureMarker::test_cosign_missing_marker_clears_when_cosign_appears

Fixes #13408

[alt-glitch]

Likely duplicate of #9925 — same root cause in bundle_content_hash() calling .encode('utf-8') on bytes content. Multiple prior fix PRs exist (#9925, #14108, #13531) for #13408.

[alt-glitch]

Likely duplicate of #9925 — same root cause in bundle_content_hash() calling .encode('utf-8') on bytes content. Multiple prior fix PRs exist (#9925, #14108, #13531) for #13408.

[helix4u]

well fun. my search didn't find any of those. i'll just close it.
new instruction to try and mitigate:
When checking whether a GitHub PR already exists for an issue, do not rely only on GitHub issue “Development” metadata, search results, or gh pr list --search. Always inspect the issue body/comments/timeline for referenced #12345 numbers and open each candidate PR directly with gh pr view <number> --repo <owner>/<repo>. If a search command fails or returns empty, treat that as inconclusive, not proof that no PR exists. Before creating a new PR for a known issue, run a direct PR search by issue number, symptom terms, function/file names, and any referenced PR numbers, then state which candidates were checked.