P2-X: Ensure P2 background consolidation + sharing pipeline meets DESIGN

[devlux76]

NOTE: DESIGN has been moved to the wiki https://github.com/devlux76/cortex/wiki

This is a super-task for completing the remaining P2 work that must satisfy the DESIGN’s background consolidation + safe sharing contract.\n\nIt should be a child of the existing P2 tracker (#70). Close each listed subtask issue as it is verified complete; this issue remains open until all checklist items are checked.\n\n### Subtasks (close the relevant issue when done)\n- [ ] Ensure Busy/Idle Scheduler + task queue operates reliably and is resilient to throwing tasks. (Related: #29)\n- [ ] Ensure HebbianUpdater properly strengthens/decays edges, enforces , and triggers salience + promotion sweep. (Related: #30)\n- [ ] Ensure FullNeighborRecalc recomputes obeying and clears dirty flags (including ensuring neighbor graph is populated). (Related: #31/#62)\n- [ ] Ensure PrototypeRecomputer recomputes prototypes/medoids and appends them to the VectorStore, including quota-based promotion sweep. (Related: #32)\n- [ ] Ensure ClusterStability detects oversized/empty communities and performs splits/merges, including deletion of orphaned volumes. (Related: #34)\n- [ ] Ensure Curiosity broadcast + P2P sharing is implemented with eligibility/PII gating, rate limiting, and safe import. (Related: #35/#63)\n- [ ] Ensure Integration test coverage validates Williams-bound resident capacity, background consolidation behavior, and safe curiosity broadcasting. (Related: #33)\n\n### Completion guidelines\n- Close each source issue (e.g., #29, #30, #31, #32, #33, #34, #35, #62) as soon as the implementation meets its acceptance criteria.\n- Keep this issue open until all checklist items are complete and the system matches the P2 design expectations.\n\n> NOTE: This is a tracking issue; it does not implement behavior itself. It exists to coordinate completion across the individual subtasks and ensure none are silently left behind.,labels:[P2: medium]