fix(desktop): add calendar chip context menus

[ComputelessComputer]

Show native sidebar-style context menus for calendar event and session chips.

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Note

Medium Risk
Context menus trigger ignore-event and cascade session deletion with undo; behavior is refactored into a shared hook but still mutates local store and filesystem on finalize.

Overview
Adds native (Tauri) context menus to calendar event and session chips, aligned with the top meeting timeline: open in a new tab, delete/ignore calendar events (including recurring series), show session folder in Finder, and delete notes.

Session deletion logic is centralized in a new useDeleteSession hook and wired from the meeting timeline and calendar session chips instead of inlined store/undo code.

Calendar day cells and chip buttons get select-none to reduce accidental text selection when right-clicking.

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[netlify]

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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