feat: improve local dev with install path (#1221)

- also add better watcher support

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **New Features**
- Added a helper that displays a local installation URL to simplify
setting up the plugin.

- **Chores**
- Updated service and container port configurations to ensure consistent
network connectivity (changed from 8080 to 5858).
- Refined container management to gracefully handle running instances
during startup.
- Improved build and installation routines for streamlined deployment
and enhanced reliability.
- Enhanced documentation to clarify installation and usage instructions
for better user experience.
- Introduced a new document outlining development workflows for better
guidance.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---
- To see the specific tasks where the Asana app for GitHub is being
used, see below:
  - https://app.asana.com/0/0/1209561202532053

plugin/docker-compose.yml

@@ -1,7 +1,7 @@
 services:
   plugin-builder:
     ports:
-      - 8080:8080
+      - 5858:5858
     build: .
     volumes:
       - ./:/app