chore(ci): fix pre-commit hook failures

Fix JSON syntax errors in .devcontainer/devcontainer.json (removed
invalid JS-style // comments) and .devcontainer/opencode.json (removed
90+ trailing commas). Apply auto-fixes for end-of-file and trailing
whitespace issues across 100+ files. Fix SIM105 ruff violations in
benchmarks/core_circuit_breaker_bench.py (use contextlib.suppress).

Note: The security fix from issue #7478 (validate_path startswith bypass)
was already delivered to master in commit e18ac5f2. This PR as currently
structured is non-atomic (35 commits across 10+ issues) and needs
significant restructure before merge. This commit only addresses the
CI/pre-commit failures.

ISSUES CLOSED: #7478

examples/actions/estimation-actor.yaml

@@ -43,4 +43,3 @@ automation_profile: trusted
 invariants:
   - "All existing tests must continue to pass"
   - "Public API signatures must not change without deprecation"
-

examples/actions/inputs-schema.yaml

@@ -56,4 +56,3 @@ inputs_schema:
         - parquet
   required:
     - stages
-

examples/actions/invariant-heavy.yaml

@@ -47,4 +47,3 @@ invariants:
   - "All findings must include reproducible steps"
   - "Secrets found during scanning must be redacted in reports"
   - "Remediation fixes must not break existing tests"
-

examples/actions/read-only.yaml

@@ -25,4 +25,3 @@ definition_of_done: |
 reusable: true
 read_only: true
 state: available
-

examples/actions/simple.yaml

@@ -16,4 +16,3 @@ definition_of_done: |
 
 reusable: true
 read_only: true
-