feat(calendar): add calendar aliases

[zacharytamas]

Summary

• Add support for calendar aliases, allowing users to map friendly names like family to full calendar IDs like 3656f8abc123@group.calendar.google.com
• New CLI commands: gog calendar alias {list,set,unset}
• All calendar commands now resolve aliases before using calendar IDs

Usage

# Set an alias
gog calendar alias set family 3656f8abc123@group.calendar.google.com

# Use the alias in any calendar command
gog calendar create family --summary "Dinner" --from "2026-01-24T18:00:00Z" --to "2026-01-24T20:00:00Z"
gog calendar events family --today
gog calendar search "birthday" --calendar family

# Aliases work in comma-separated lists too
gog calendar freebusy family,work --from "..." --to "..."

# List and remove aliases
gog calendar alias list
gog calendar alias unset family

Config

Aliases are stored in ~/.config/gog/config.json:

{
  "calendar_aliases": {
    "family": "3656f8abc123@group.calendar.google.com"
  }
}

Test plan

• Unit tests for config CRUD operations
• Unit tests for CLI commands
• Unit tests for alias resolution helper
• All existing tests pass

[salmonumbrella]

Great addition. Thanks @zacharytamas

[visionik]

Hi Zachary -

Great idea.

Two things:

1. Your PR has a CI failure check (see above). Can you fix and update?

2. I am trying to decide if we should merge this as is, or create a more holistic alias system so you can use aliases anywhere in gog. For eample

gog docs family-history sed ...

Thoughts?

[visionik]

@zacharytamas still out there? Would like to get the CI checkes cleared and wonder if you have thoughts on global sogcli alias support.

[salmonumbrella]

Opened a continuation PR because this branch cannot be updated from my account and CI needed cleanup: #393

This keeps the same feature scope and passes current CI locally (make ci).

Tagging for visibility: @zacharytamas @visionik