fix(P30): temp dir isolation + forge-agnostic APIs + static-key override (P1-8, P1-9, S1)

---ci---
project: acdl
phase: 30
milestone: v1.8
status: execute
---/ci---

P1-8: run_platform.sh now emits adapter output to $WORK/tf (per-run temp
dir), not the committed terraform/spike/ directory. The committed
terraform/spike/*.tf files are removed — they were scratch artifacts.
Deploy workflow artifact upload path updated to /tmp/acdl_platform_run_v18/tf/.
P1-9: contract_ingestor.py now reads GITHUB_API_BASE env for forge-agnostic
API URLs. _forge_type() detects GitHub vs Gitea. Search URL is branched
(GitHub uses /search/issues, Gitea uses /repos/{owner}/{repo}/issues).
S1: Deploy workflow configure-aws-credentials step restructured as a single
conditional step. OIDC when no static key (role-to-assume), static-key
when ACDL_AWS_ACCESS_KEY_ID present (access-key-id/secret-access-key inputs).
Both deploy workflows remain byte-identical.

Tests: +8 (292 -> 300). All pass. run_platform.sh --check-only green.

.github/workflows/deploy.yml

@@ -91,14 +91,13 @@ jobs:
           echo "deb [signed-by=/usr/share/keyrings/hashicorp.gpg] https://apt.releases.hashicorp.com $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/hashicorp.list
           sudo apt-get update && sudo apt-get install -y terraform=1.9.*
 
-      - name: Configure AWS credentials (OIDC default)
+      - name: Configure AWS credentials (OIDC default + static-key override)
         uses: aws-actions/configure-aws-credentials@v4
         with:
-          role-to-assume: arn:aws:iam::${{ secrets.ACDL_AWS_ACCOUNT_ID }}:role/acdl-deploy-${{ github.repository_id }}
+          role-to-assume: ${{ secrets.ACDL_AWS_ACCESS_KEY_ID == '' && format('arn:aws:iam::{0}:role/acdl-deploy-{1}', secrets.ACDL_AWS_ACCOUNT_ID, github.repository_id) || '' }}
           aws-region: us-east-1
-        env:
-          ACDL_AWS_ACCESS_KEY_ID: ${{ secrets.ACDL_AWS_ACCESS_KEY_ID }}
-          ACDL_AWS_SECRET_ACCESS_KEY: ${{ secrets.ACDL_AWS_SECRET_ACCESS_KEY }}
+          access-key-id: ${{ secrets.ACDL_AWS_ACCESS_KEY_ID }}
+          secret-access-key: ${{ secrets.ACDL_AWS_SECRET_ACCESS_KEY }}
 
       - name: Run the platform pipeline
         working-directory: ${{ github.workspace }}
@@ -136,7 +135,7 @@ jobs:
         uses: actions/upload-artifact@v4
         with:
           name: acdl-terraform
-          path: platform/terraform/spike/*.tf
+          path: /tmp/acdl_platform_run_v18/tf/*.tf
           if-no-files-found: warn
 
       - name: Upload platform log