feat: add apple search ads commands

[adressop6789-max]

What

Adds an adapty asa topic for managing Apple Search Ads: campaigns, ad groups,
keywords, negative keywords, search terms, ads, product pages, creatives,
rule-based automations and metrics.

Highlights

• New ASA service client — talks to https://api-asa-admin.adapty.io/api/v1/cli
  (override via ADAPTY_ASA_API_URL). No --app flag: scope is the token's company.
• Safe writes — every mutating command prints the exact request body and asks
  for confirmation; --yes skips the prompt for scripts, and under --json or a
  pipe the command refuses instead of hanging.
• Batched keyword operations — max 100 items per call, partial rejections
  reported per item with Apple's reason.
• Metrics — asa metrics / asa metrics overview with entity levels, cohort
  renewal windows (--by-days, max 16) and --order-by-day ranking.
• Scoped list filters — --campaign-group / --app / --campaign / --ad-group /
  --status / --search narrow the query itself, not the printed page.

Purely additive

Existing behavior is untouched: Developer API commands, URLs and error parsing work
exactly as before. ApiClient extensions (defaultBaseUrl, errorFormat, query
params on POST/PUT) are opt-in with defaults matching the old behavior, covered by
dedicated tests.

Docs

README, the Claude Code skill (skills/adapty-cli/SKILL.md) and
references/cli-commands.md updated with the full asa command reference.