Add agentic workflow recompilation instruction

Ensure all coding agents know to run 'gh aw compile' and 'apm compile'
after modifying workflow files, preventing stale integration file CI failures.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: mrjf

.apm/instructions/agentic-workflows.instructions.md

@@ -0,0 +1,16 @@
+---
+description: "Agentic workflow recompilation: always recompile after changing workflow files"
+---
+
+# Agentic Workflows
+
+After modifying any `.md` workflow file under `.github/workflows/`, always
+recompile both agentic workflows and APM integration files before committing:
+
+```bash
+gh aw compile
+apm compile
+```
+
+Commit the regenerated `.lock.yml` and integration files together with your
+changes. The CI `APM Self-Check` job will fail if generated files are stale.

.github/copilot-instructions.md

@@ -1,7 +1,22 @@
 <!-- Generated by APM CLI from .apm/ primitives -->
-<!-- Build ID: 791e09362ff0 -->
+<!-- Build ID: cdb5b8cab974 -->
 <!-- APM Version: 0.12.4 -->
 
+<!-- Source: .apm/instructions/agentic-workflows.instructions.md -->
+# Agentic Workflows
+
+After modifying any `.md` workflow file under `.github/workflows/`, always
+recompile both agentic workflows and APM integration files before committing:
+
+```bash
+gh aw compile
+apm compile
+```
+
+Commit the regenerated `.lock.yml` and integration files together with your
+changes. The CI `APM Self-Check` job will fail if generated files are stale.
+<!-- End source: .apm/instructions/agentic-workflows.instructions.md -->
+
 <!-- Source: .apm/instructions/linting.instructions.md -->
 # Linting (canonical contract)