fix(P59): 3 pipeline-readiness fixes — resolver id, schema inputs, CI creds

3 fixes found during the pipeline-readiness audit (all 24 example contracts
now resolve + adapt + pass --check-only):

1. core/contract_resolver.py: L1 resolver resource id now replaces underscores
   with hyphens (task_definition → task-definition), matching the L2 resolver
   pattern. The stack schema requires ^[a-z][a-z0-9-]*$ (no underscores).

2. schemas/stack.schema.json: relaxed input type constraint to allow array +
   object (was string/number/boolean only). Real-world inputs include lists
   (monitored_endpoints, static_checks, rules) and dicts (alert_channels).

3. scripts/run_platform.sh: AWS creds loading is now conditional — if
   AWS_ACCESS_KEY_ID/AWS_SECRET_ACCESS_KEY are already set (by the CI
   configure-aws-credentials action), skip loading .env.secrets. This makes
   the --apply/--destroy modes work in CI without the gitignored secrets file.

Regression: 479 passed, 0 skipped, 5 deselected.

---ci---
project: acdl
phase: P59
milestone: v1.11
status: execute
---/ci---

schemas/stack.schema.json

@@ -92,7 +92,7 @@
         "inputs": {
           "type": "object",
           "description": "Input values keyed by the module's declared inputs. Free-form in v1 (validated at contract->stack resolution against the module registry); typed per-module in v1.2.",
-          "additionalProperties": {"type": ["string", "number", "boolean"]}
+          "additionalProperties": {"type": ["string", "number", "boolean", "array", "object"]}
         },
         "outputs": {
           "type": "object",