Changelog

The cloud sync was hitting 429 rate limits and not properly backing off,

causing repeated error spam. The C# refresh timer kept calling GetQuota()

every 15 seconds even during rate limits, generating cascading 429 errors.

Rust API client (api_client.rs):

• Added sliding window request counter that enforces 75% of the server's

advertised rate limit (450 req/60s instead of 600). Proactively throttles

before hitting the server limit.

• Changed 429 backoff to use 2x the server's Retry-After header with a

60-second floor. Previously used 1x which allowed immediate re-triggering.

• Counter limits are updated from server config on sync engine startup.

Rust FFI layer:

• Added PrivStackError::RateLimited (= 36) to distinguish rate limits from

generic CloudSyncError. Previously all rate limit errors mapped to

CloudSyncError and C# couldn't tell them apart.

• Rate limit errors now log as WARN instead of ERROR (expected transient).
• CloudSyncStatus now includes is_rate_limited and rate_limit_remaining_secs

fields, populated from the API client's gate state.

C# desktop:

• CloudSyncSettingsViewModel.RefreshStatusAsync() checks is_rate_limited

from status and skips all API calls (quota, devices, tokens) when true.

This eliminates the cascading 429 errors from the refresh timer.

• Catches PrivStackError.RateLimited specifically instead of falling through

to the generic exception handler.

• Status refresh timer slows from 15s to 30s during rate limit pause (still

updates the remaining-seconds display but doesn't hit the API).

• Added IsRateLimited and RateLimitDisplay observable properties for UI.

Rust v1.15.2, Desktop v1.66.3

• Add IsDetached property and RequestReattach command to AiSuggestionTrayViewModel
• Show reattach button (dock icon) in tab strip when tray is detached
• Add content margin (8px sides/bottom) to AiTrayWindow for breathing room
• Wire ReattachRequested event in MainWindow detach/reattach lifecycle
• Version bump 1.66.1 → 1.66.2

When the AiSuggestionTray was reparented into the floating window,

its XAML binding DataContext="{Binding AiTrayVM}" tried to resolve

against the floating window's DataContext (AiSuggestionTrayViewModel),

which doesn't have an AiTrayVM property. This caused the binding to

fail, leaving DataContext null and all internal panel visibility

bindings broken (both Chat and Intents panels visible simultaneously,

link picker showing).

Fix: explicitly set trayControl.DataContext = vm.AiTrayVM after

removing from the inline grid, bypassing the XAML binding path.

Also close the link picker before reparenting for clean state.

Adds SpellCheckAdorner (wavy underlines for misspelled words in TextBox),

SpellCheckBehavior (attached behavior to enable spell check), autocorrect

service, and spell check rendering utilities. Integrates spell check into

RichTextEditor with debounced recheck and dictionary change handling.

Fixes Timer ambiguity (System.Timers vs System.Threading) in SpellCheckAdorner

and RichTextEditor.SpellCheck by fully qualifying System.Timers.Timer. Fixes

IsAttachedToVisualTree → GetVisualRoot() and GetTemplateChildren →

GetVisualDescendants for Avalonia 11.3.x compatibility.