docs(agents): launch P1 contract spine

[blakinio]

Purpose

Launch the accepted four-package P1 contract-spine wave from exact post-aggregation main@55fec043758e1928fd5d39831322a0c21f47589b.

Dispatch

• tools(playability): generate Canary Current source index #154 Canary source index — head c86524850644e9d33373c88358a4eff904190e7f;
• feat(game-domain): define canonical gameplay contracts #155 game-domain contracts — head 074570a453dd6e8626b6c16ebf51d38bad2d8d1a;
• feat(asset-runtime): verify and index synthetic packs #156 asset pack runtime — head 326805dd1d18f18172365ec632b7a71e470ecb96;
• feat(input): define normalized action contracts #157 input actions — head f2dbb5b983131d1e72464f9a95ad5d4f8a3b7d83.

All workers begin from the same base, own only exclusive paths and have no shared integration lease at launch.

Safety

Coordinator task only. No implementation, source, manifest, lockfile, workflow, app composition or shared catalogue change. PR #23-owned paths remain untouched.

Validation

Head f5bb29b6ae0a2aba24d5e7c2851e05a3ccd2dca9:

• exactly one changed task path;
• four worker task/branch/draft PR lanes reconciled;
• comments, reviews and unresolved threads: none;
• repository CI run 30716862550;
• CI / Required job 91413983631.