refactor: remove kind from resource class apispec

[SalimKayal]

Summary

This PR simplifies #1388
by removing the redundant kind field from resource classes.

Since every class must match its parent pool's remote kind, exposing kind on each
class is unnecessary. Local vs remote is now derived from the pool.

Changes

• Remove kind from all resource-class schemas and reuse ResourceClassProperties
  via allOf; regenerate apispec.py.
• Drop local from RemoteConfigurationKind; None now means local.
• Derive class kind from pool_kind in validators and from the parent pool in
  db.py/orm.py.
• Keep the FirecREST integer-CPU guard at validation time and add an int cast at
  session submission in notebooks/core_sessions.py.
• Update unit tests and base API tests.

[coveralls]

Coverage Report for CI Build 31175062154

Warning

No base build found for commit 1856daa on salimkayal/feat/expend-resource-class-apispec-for-remote-sessions.
Coverage changes can't be calculated without a base build.
If a base build is processing, this comment will update automatically when it completes.

Coverage: 85.089%

Details

• Patch coverage: 3 uncovered changes across 1 file (25 of 28 lines covered, 89.29%).

Uncovered Changes

File	Changed	Covered	%
components/renku_data_services/crc/db.py	5	2	40.0%
Total (6 files)	28	25	89.29%

Coverage Regressions

Requires a base build to compare against. How to fix this →

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Coverage Stats

Relevant Lines:	31721
Covered Lines:	26991
Line Coverage:	85.09%
Coverage Strength:	0.85 hits per line

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💛 - Coveralls