v3.0.16 — bug fixes (#964)

* fix(mcp): MCP RFC compliant for more strict clients

* fix(mcp): serve flat /.well-known/oauth-protected-resource for ChatGPT reconnect

Clients such as ChatGPT probe the flat well-known URL on every fresh discovery
cycle (i.e. after a full disconnect/reconnect where cached OAuth state is cleared).
The SDK's mcpAuthMetadataRouter only serves the path-based form
/.well-known/oauth-protected-resource/mcp, so the flat probe returned 404.

Without the resource metadata, ChatGPT fell back to the issuer URL as the
resource parameter (https://…/ instead of https://…/mcp). The authorize handler
then rejected it with invalid_target and redirected back to ChatGPT's callback
with an error — showing the user the TREK home page instead of the consent form.

Add an explicit GET handler for the flat URL that returns the same protected
resource metadata, so the resource URI is discovered correctly on the first probe.

* fix(mcp): fix OAuth popup blank page — SW denylist and COOP header

Service worker was intercepting /oauth/authorize navigate requests
(not in denylist), serving index.html, and React Router's catch-all
redirected to / instead of the SDK authorize handler.

Helmet's default COOP: same-origin isolated the /oauth/consent popup
from its cross-origin opener, making window.opener null and breaking
the popup-based OAuth completion signal for ChatGPT and similar clients.

* fix(ntfy): encode non-Latin-1 header values with RFC 2047 to prevent ByteString crash

Todo/trip names containing chars like → or € (and non-Latin-1 locale templates
for Czech, Chinese, Russian, etc.) caused the Fetch API to throw when setting
the ntfy Title header. Apply RFC 2047 base64 encoded-word encoding for any
header value containing chars above U+00FF; ntfy decodes this automatically.

* docs(mcp): document Cloudflare bot detection blocking ChatGPT MCP requests

Add Cloudflare WAF note to MCP-Setup and a full troubleshooting entry covering
root cause (IP reputation + UA heuristics), free-plan limitation (disable Bot
Fight Mode entirely, with explicit warning), and paid-plan WAF skip rule with
the full expression syntax and path table for all MCP/OAuth/.well-known routes.

* fix(pwa): detect upstream proxy auth challenges and recover gracefully

Behind Cloudflare Zero Trust or Pangolin, cross-origin auth redirects on
/api/* calls surface as CORS errors (error.response === undefined) that
the existing 401 interceptor never catches, leaving the PWA stuck with
network-error toasts instead of re-authenticating.

New connectivity module probes /api/health every 30s using fetch with
cache:no-store and inspects Content-Type to reliably detect whether the
server is reachable vs intercepted by an upstream proxy.

axios interceptor changes:
- On !error.response + navigator.onLine: run probeNow(); if the health
  probe also fails (proxy is intercepting all requests), trigger a guarded
  window.location.reload() so the edge proxy can intercept the top-level
  navigation and run its auth flow (covers CF Access and Pangolin 302 mode)
- On error.response status 401 with text/html body: same reload path,
  covering Pangolin header-auth extended compatibility mode which returns
  401+HTML instead of a 302 redirect. TREK own 401s are always JSON so
  there is no collision with the existing AUTH_REQUIRED branch.
- sessionStorage flag prevents reload loops; cleared on any successful
  response so the guard resets after re-auth.

/api/health excluded from SW NetworkFirst cache (vite.config.js regex)
and Cache-Control: no-store added server-side so probes always hit the
network and cannot be served stale from the 24h api-data cache.

LoginPage caches last-known appConfig in localStorage so the SSO button
renders in OIDC+UN/PW dual mode even when the config fetch is intercepted
by the proxy. Auto-redirect to IdP skipped when config comes from cache
to avoid redirect loops while the proxy is challenging.

Fixes discussion #836.

* fix(files): add bottom-nav padding to files tab wrapper on mobile

* fix(budget): expose toolbar on mobile so users can add budget categories

* fix(pwa): unregister SW before proxy-reauth reload so Pangolin can challenge

WorkBox's NavigationRoute served the cached SPA shell on window.location.reload(),
meaning Pangolin/CF Access never saw the navigation and the app was left stuck
showing stale offline data. Unregistering the SW first lets the navigation reach
the network so the upstream proxy can run its auth flow.

Also rebuilds server/public with corrected sw.js (health excluded from
NetworkFirst, /oauth/ and /.well-known/ added to NavigationRoute denylist).

* chore: remove committed build artifacts from server/public

Dockerfile and Proxmox community script both rebuild client/dist and copy
it into server/public at build time — committed artifacts were never used.
Replace with .gitkeep and add server/public/* to .gitignore.

* chore: add build-from-sources script

wiki/MCP-Setup.md

@@ -6,6 +6,8 @@ This page explains how to connect an AI assistant to your TREK instance. TREK su
 
 ![MCP Setup](assets/MCPConfig.png)
 
+> **Cloudflare users:** If your TREK instance is proxied through Cloudflare, Bot Fight Mode and Super Bot Fight Mode will block MCP requests from ChatGPT. Claude.ai is not affected. See [Troubleshooting → MCP requests blocked by Cloudflare WAF](#mcp-requests-blocked-by-cloudflare-waf-bot-fight-mode) for the fix.
+
 ## Option A: OAuth 2.1 (recommended)
 
 OAuth 2.1 is the preferred connection method. You grant specific scopes during the consent step and no token management is required afterward — TREK issues short-lived access tokens and automatically rotates refresh tokens.