docs: clarify dev hosts and deployment guidance

.github/copilot-instructions.md

@@ -1,26 +1,13 @@
 # MedAssist-ng - Copilot Entry Point
 
-## VERY IMPORTANT - Prioritized Constraints
+This file is intentionally thin. `AGENTS.md` is the canonical governance file for this repository.
 
-**First: Update Memory and Reports**
-- Always keep agent work memory updated in `doku/memory_notes.md` so progress and decisions remain recoverable across context loss.
-  - If `doku/memory_notes.md` is missing, create it immediately.
-- Always keep a user-facing work report updated in `doku/report.md` so completed work is easy to review.
-  - If `doku/report.md` is missing, create it immediately.
-- This memory/report rule replaces the previous `doku/APP_BEHAVIOR.md` persistence requirement.
-
-**Second: Follow Governance Rules**
-- Consult `AGENTS.md` for governance, workflow, and skill rules when that file exists in the workspace.
-
-When `AGENTS.md` exists in the workspace, use it as the single source of truth for governance, workflow, and skill rules.
+If rules differ between files, follow `AGENTS.md`.
 
 ## Required Startup Steps
 
 1. Read `AGENTS.md` first when it exists in the workspace.
-2. If `AGENTS.md` exists, identify triggered skills from it and read each referenced `SKILL.md` before making changes.
-3. Follow delegation boundaries exactly (`@testing-manager` for testing, `@release-manager` for release orchestration).
-4. When work moves into a different thematic area, create or switch to a dedicated local branch or worktree before editing code, and reuse the same branch/worktree for follow-up work inside that same theme.
-
-## Scope
-
-This file intentionally stays minimal to prevent duplicated or conflicting instructions.
+2. Ensure `doku/memory_notes.md` and `doku/report.md` exist and keep them updated during meaningful work. These files are local-only and must not be staged or committed unless explicitly requested.
+3. Identify triggered skills from `AGENTS.md` and read only the matching `SKILL.md` files before making changes.
+4. Follow delegation boundaries from `AGENTS.md`: `@testing-manager` for testing work and `@release-manager` for release orchestration, including the documented fallback protocol when a required specialist is unavailable.
+5. Keep all non-canonical instruction files brief and aligned with `AGENTS.md`; do not duplicate full governance here.

.github/workflows/docker-build.yml

@@ -24,6 +24,8 @@ on:
 
 concurrency:
   group: docker-build-${{ github.ref }}
+  # Cancel older runs on the same ref so the shared branch tag stays aligned
+  # with the newest commit instead of racing older builds against newer ones.
   cancel-in-progress: true
 
 # Default minimal permissions