fix(gateway): correct sys.path insertion in all migrated platform adapters (cron namespace collision)

[teknium1]

Summary

Gateway no longer crashes on startup with ModuleNotFoundError: No module named 'cron.scheduler_provider'.

Root cause: commit 5600105478 migrated the slack/discord/whatsapp/telegram/raft adapters from gateway/platforms/ to plugins/platforms/. Each adapter does sys.path.insert(0, parents[2]) — one level deeper now, so parents[2] resolves to plugins/ instead of the repo root. With plugins/ on sys.path[0], import cron resolves to the plugins/cron/ chronos-provider package (which has no scheduler_provider submodule), so the first from cron.scheduler_provider import … during start_gateway() raises ModuleNotFoundError.

Changes

• plugins/platforms/{discord,raft,slack,whatsapp,telegram}/adapter.py: parents[2] → parents[3] so each inserts the repo root, not plugins/.

gateway/platforms/base.py correctly keeps parents[2] (it lives one level shallower, so parents[2] is already the repo root there).

Attribution

• @kyssta-exe (fix(gateway): correct sys.path insertion in plugins to prevent cron namespace collision (#49410) #49431) — original fix for the discord + raft adapters; commit cherry-picked with authorship preserved.
• Follow-up commit widens the same one-line fix to the three remaining affected adapters (slack, whatsapp, telegram) that fix(gateway): correct sys.path insertion in plugins to prevent cron namespace collision (#49410) #49431 missed.
• fix: prevent cron/scheduler_provider ModuleNotFoundError from sys.path shadowing #49414 (@ochsec) took a different approach — pre-importing cron.* at module level to cache sys.modules before the bad insert. That treats the symptom (the broken parents[2] insert stays, so any module imported after a platform adapter is still at risk) and bundled an unrelated kanban change, so this PR fixes the root cause instead.

Validation

	Before	After
import cron.scheduler_provider after any of the 5 adapters loads	ModuleNotFoundError	resolves to repo cron/scheduler_provider.py
sys.path[0] after adapter import	plugins/	repo root

E2E: simulated each adapter's sys.path.insert and confirmed cron.scheduler_provider resolves to the real package for all 5. tests/cron/test_scheduler_provider.py + tests/gateway/test_cron_fire_webhook.py — 25/25 pass.

Fixes #49410, #49824.

Infographic

[github-actions]

🔎 Lint report: hermes/hermes-1cc1e50a vs origin/main

ruff

Total: 0 on HEAD, 0 on base (➖ 0)

🆕 New issues: none

✅ Fixed issues: none

Unchanged: 0 pre-existing issues carried over.

ty (type checker)

Total: 11278 on HEAD, 11276 on base (🆕 +2)

🆕 New issues (2):

Rule	Count
unresolved-attribute	2

First entries

run_agent.py:2984: [unresolved-attribute] unresolved-attribute: Object of type `Self@get_credits_spent_micros` has no attribute `_credits_session_start_micros`
tests/run_agent/test_credits_notices_toggle.py:76: [unresolved-attribute] unresolved-attribute: Unresolved attribute `_credits_session_start_micros` on type `AIAgent`

✅ Fixed issues (1):

Rule	Count
invalid-assignment	1

First entries

tests/run_agent/test_credits_notices_toggle.py:76: [invalid-assignment] invalid-assignment: Object of type `None` is not assignable to attribute `_credits_session_start_micros` of type `int`

Unchanged: 5912 pre-existing issues carried over.

Diagnostics are surfaced as warnings — this check never fails the build.

[alt-glitch]

Related: #49431 (@kyssta-exe — original parents[2]->parents[3] fix for discord+raft), #49414 (@ochsec — alternate module-level pre-import approach), and the bug reports #49410 / #49824 this fixes. This PR widens the root-cause fix to all 5 migrated adapters (slack/whatsapp/telegram added) with authorship preserved. Not a duplicate of the community PRs — it's the authoritative consolidation.