fix(cli): --insecure also skips TLS certificate verification

[GareArc]

Resolves ENG-708

Summary

difyctl auth login --insecure only allowed http:// hosts. Against a self-signed https:// host (e.g. an internal Dify instance) it still failed with self signed certificate. --insecure now also skips TLS certificate verification, so it covers both "no TLS" and "untrusted cert" as one blanket flag — consistent with how --insecure/-k works in most CLIs.

• http/proxy.ts: builds an undici Agent/EnvHttpProxyAgent with rejectUnauthorized: false when insecure is set
• Persisted per-host (insecure_tls, same pattern as the existing scheme field) so authenticated commands after login don't need --insecure again — and a later secure login to the same host clears it
• Threaded through login, logout, authed commands, and the version/compat probe via a shared activeHostInfo() helper

Test plan

• pnpm type-check, pnpm lint:fix, pnpm test (1217 passed, 0 failed)
• Manual smoke test against a real self-signed HTTPS server: rejected without --insecure, accepted with it

[codecov]

Codecov Report

❌ Patch coverage is 70.73171% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 85.39%. Comparing base (6c0aa3e) to head (af4f11e).
⚠️ Report is 10 commits behind head on main.

Files with missing lines	Patch %	Lines
cli/src/commands/_shared/authed-command.ts	0.00%	5 Missing ⚠️
cli/src/version/enforce.ts	20.00%	4 Missing ⚠️
cli/src/commands/auth/logout/index.ts	0.00%	2 Missing ⚠️
cli/src/commands/auth/login/index.ts	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #38531      +/-   ##
==========================================
+ Coverage   85.34%   85.39%   +0.05%     
==========================================
  Files        5012     5169     +157     
  Lines      265733   270146    +4413     
  Branches    50513    51596    +1083     
==========================================
+ Hits       226779   230684    +3905     
- Misses      34506    35014     +508     
  Partials     4448     4448              

Flag	Coverage Δ
cli	88.48% <70.73%> (?)

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