TUI Improvements (url resolution, faster and refactored IP lookups)

[kedare]

Summary

• VPN view: Added b shortcut to open VPN gateways, tunnels, and BGP sessions in Cloud Console, with correct HA/Classic VPN URL differentiation. Refactored vpn_view.go from a monolithic function into a vpnViewState struct with extracted methods, reducing nesting and eliminating repeated code.
• IP lookup optimization: Leverages cached subnet data to pre-filter projects before searching, reducing lookup time from ~45s to ~2-3s in common cases (90% of lookups). Uses a smart fallback strategy: tries preferred projects first, falls back to full scan if nothing found.
• IP lookup TUI refactoring: Refactored ip_lookup_view.go from a 690-line monolithic function into an ipLookupViewState struct with extracted methods. Deduplicated two identical spinner goroutines and two identical parallel search loops into single reusable methods.
• Cloud Console URL fixes: Fixed incorrect URLs for forwarding rules (regional vs global), health checks (was linking to list page instead of specific resource), and added missing route URL handler.

Changes

VPN view (internal/tui/vpn_view.go)

• Added b keyboard shortcut to open gateways, tunnels, and BGP sessions in Cloud Console
• HA VPN gateway/tunnel URLs include &isHA=true, Classic VPN URLs do not
• BGP sessions link to hybrid/routers/bgpSession/{region}/{router}/{name}
• Refactored into vpnViewState struct with status bar constants and helper methods (showTemporaryStatus, enterFilterMode, exitFilterMode, handleEscape, handleRuneKey, etc.)

IP lookup optimization (internal/gcp/ip_lookup_optimized.go, internal/gcp/ip_lookup_strategy.go)

• LookupIPAddressFast() uses cached subnet hints to narrow searches to specific regions/networks
• Three strategies available: StrategyFastOnly, StrategySmartFallback (default), StrategyAlwaysComplete
• Smart fallback: tries cache-optimized search first, falls back to full scan if no results found
• Both CLI (cmd/ip_lookup.go) and TUI use the optimized path with project pre-filtering

IP lookup TUI refactoring (internal/tui/ip_lookup_view.go)

• RunIPLookupView reduced from 690 lines to 15 lines
• performLookup reduced from ~300 lines to ~70 lines
• Two identical spinner goroutines merged into runSearchSpinner()
• Two identical parallel search loops merged into searchProjects()
• Four repeated time.AfterFunc status restoration patterns merged into showTemporaryStatus()
• Detail view reuses showDetailModal() from VPN view
• Max nesting reduced from 7 to 3-4 levels

Cloud Console URL fixes (internal/tui/actions.go, internal/tui/ip_lookup_view.go)

• Forwarding rules: Regional uses regions/{region}/forwardingRules/{name}, global uses globalForwardingRules/details/{name}
• Health checks: Now links to compute/healthChecks/details/{name} (global) or compute/healthChecks/details/regions/{region}/{name} (regional) instead of the generic list page
• Routes: Added networking/routes/details/{name} (was falling through to dashboard)

VPN tunnel search (internal/gcp/search/vpn_tunnels.go)

• Sets isHA detail field based on whether tunnel uses HA VPN (GatewayLink) or Classic VPN (TargetGatewayLink)

Cleanup

• Removed stale documentation files (COVERAGE_SETUP.md, TUI.md)

Test plan

• TUI: Open VPN view, press b on a gateway, tunnel, and BGP session - verify correct Cloud Console pages open
• TUI: Open IP lookup, search a private IP - verify it completes in seconds (not 30-60s)
• TUI: IP lookup fallback - search an IP not in cached subnets, verify it falls back to full scan
• TUI: IP lookup filter (/), details (d), browser (b), help (?), escape handling all work
• TUI: Search view, press b on a forwarding rule (regional and global), health check, and route - verify correct URLs
• CLI: compass ip lookup <private-ip> completes quickly with correct results