chore: drop hindsight-hermes integration (#931)
* chore: drop hindsight-hermes integration in favor of native Hermes memory provider
Hermes Agent now ships with a native Hindsight memory provider (NousResearch/hermes-agent#5094),
making our pip-installable hindsight-hermes package redundant.
Removes:
- hindsight-integrations/hermes/ (source, tests, config)
- CI job, release script entry, changelog generator references
- Cookbook page and pip package changelog (referenced deleted code)
Keeps:
- Integration docs (updated by #881 for native provider)
- Blog posts (historical, already have deprecation notices)
- Sidebar/banner entries (still valid for native integration)
* fix(docs): remove broken cookbook link to deleted hermes-memory page