feat(stacks): state-aware sidebar context menu and Open App action (#368)

* feat(stacks): state-aware sidebar context menu and Open App action

- Context menu now adapts to stack state: running stacks show
  Stop/Restart/Update, stopped stacks show Deploy only
- Added "Open App" shortcut to open a stack's web UI directly
  from the sidebar (visible when running with a published port)
- Backend bulk status endpoint enriched with mainPort detection
- Reduced manual image update check cooldown from 10 to 2 minutes
- Rate limit error message now derives from the configured constant

* fix(stacks): use const for bulkPorts (prefer-const lint)

CHANGELOG.md

@@ -4,6 +4,19 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Added
+
+* **stacks:** state-aware sidebar context menu — actions now adapt to stack state (running stacks show Stop/Restart/Update, stopped stacks show Deploy)
+* **stacks:** "Open App" action in sidebar context menu — quickly open a stack's web interface without navigating to the detail view
+* **stacks:** bulk status endpoint now returns detected web port per stack for Open App support
+
+### Changed
+
+* **updates:** reduced manual image update check cooldown from 10 minutes to 2 minutes
+* **updates:** rate limit error message now dynamically derives from the configured cooldown constant
+
 ## [0.36.0](https://github.com/AnsoCode/Sencho/compare/v0.35.0...v0.36.0) (2026-04-04)