Refactor load testing scripts to support Bash and PowerShell

- Updated README.md to reflect changes in load testing commands and added usage examples for Bash scripts.
- Converted PowerShell load testing scripts to Bash equivalents for better cross-platform compatibility.
- Added new Bash scripts: run-loadtests.sh, summarize-artillery.sh, and summarize-k6.sh to mirror existing PowerShell functionality.
- Updated admin-api.js and ws-chat.yml for consistency and improved performance metrics reporting.
- Enhanced error handling and output formatting in summary scripts for better readability.

CHANGELOG.md

@@ -6,10 +6,12 @@
 
 ### Added
 
+- **Bash equivalents of Windows scripts**: Added `scripts/cache-hit-ratio.sh`, `scripts/check-env.sh`, `scripts/check-tokens.sh`, and `scripts/loadtest/run-loadtests.sh`, `scripts/loadtest/summarize-artillery.sh`, `scripts/loadtest/summarize-k6.sh` — Linux/macOS ports of the existing PowerShell scripts (the `.ps1` files are retained).
 - **Transient presence flash**: Join/leave announcements now appear as a 3-second flash at the top of the chat panel (`#chat-flash`) with a fade-out, instead of permanent chat rows. Presence indicators still update from the same events.
 
 ### Changed
 
+- **Docs condensed and de-Windows'd**: Removed Windows/PowerShell-specific instructions from the docs and condensed the longest documents into tighter, bash-first guides — `SETUP.md`, `DEPLOYMENT.md`, `API.md`, `MONITORING.md`, `STREAMING.md`, `COOLIFY.md`, `incident-runbook.md`, `operations/scaling-performance-playbook.md`, `architecture/README.md`, and the Prometheus metrics inventory. `scripts/loadtest/README.md` now documents the bash load-test helpers.
 - **System messages no longer persisted**: The chat backend no longer stores `system`-type messages; chat history and the admin chat-log table only contain real chat messages (moderation actions remain in the audit log).
 - **Reconnect grace period**: Disconnects schedule a delayed "left" announcement (5s); a reconnect within 5s cancels it and skips "joined", eliminating join/leave spam on brief reconnects.
 - **HLS segment duration 2s**: Default `HLS_SEGMENT_DURATION` changed from 6 to 2 and `HLS_WINDOW_SIZE` from 24 to 12 (2s × 12 = 24s live window), reducing end-to-end latency; the 2s GOP was already in place.