feat(agents-api): initialize inline Skills across native runtimes

[SaladDay]

Result

Environment Templates and standalone hosted Sessions can initialize inline Skill ZIPs. Core validates and encrypts immutable content, returns safe metadata and uses one Runtime initializer; the Codex, Claude Code and MiniMax Code adapters expose installed Skills through their native discovery paths. Updates/deletion do not change an existing Session, and recovery does not reinstall Skills.

The batch includes bounded archive admission, installed-content protection, adapter-specific activation limits, the database migration/generated contracts and usage/coverage documentation. No product changes or Provider operations are added. Skill references/version resources, generic Plugins, capability directories, system packages and restricted networking remain explicit gaps.

Validation

• make check, make openapi, make sqlc-generate, PostgreSQL/API/archive tests and Claude SDK tests/build passed on zju_a100_2. The final narrow Codex discovery guard passed targeted tests and a rebuilt real-model template run.
• Fixed OpenAI SDK 3.13.0/raw HTTP against standalone Core and real Docker Runtimes passed Codex/Kimi (template and inline), Claude/Kimi and MiniMax Code/MiniMax-M3 (template). Checks cover native Skill/helper execution, Files/Artifacts, confidential metadata and tenant isolation, frozen snapshots/retries, credential/staging and write denial, cancellation, Core/Runtime restart and retained history. All completed runs reclaimed their resources.
• The shared initializer passed in an actual Docker container and E2B VM. The unchanged Provider path did not trigger a repeat of the full E2B model matrix. The standard gate's optional native build probe remains skipped; real native/model acceptance ran separately.
• Docker packaging reused qualified base images after registry DNS failure, with freshly built candidate components. Initial permission failures and prior MiniMax probe failures remain recorded rather than counted as passes.

Evidence: ~/.parsar/remediation/20260920/environment-template-skills/; task ENV-TEMPLATES-SKILLS-001 in the board. Full protocol compatibility is not claimed.

Review

Fresh independent GPT-6 Astra high reviewed the complete diff against 6c801316858b120d09668b144861959ed1b030df with requirements, criteria, boundaries and repository rules only. No actionable findings. Independent archive/Codex-layout, API/creation-identity and PostgreSQL frozen-snapshot tests passed; the reviewer inspected existing live evidence without repeating the live-model matrix or full gate.