refactor!: core and cli installer

[wangl-cc]

Features:

• Introduce the core-installer feature to disable core installation.

Refactors:

• Transform find_lib/resource into methods of Dirs.
• Add a global DIRS variable to avoid pass it everywhere.
• Move constants to a separate module.

BREAKING CHANGES:

• Replace the self feature with cli_installer.
• Make maa update reject updating MaaCore installed at non-standard locations.
• Change Version JSON files to adopt multiple channels, resembling the version JSON of MaaCore.
• Remove deprecated field channel in cli.toml.
• Remove all installer-related environment variables. Users can now specify them either in the configuration file or as command-line arguments.

[codecov]

Codecov Report

Attention: 276 lines in your changes are missing coverage. Please review.

Comparison is base (c915139) 25.96% compared to head (fd587c9) 31.34%.

❗ Current head fd587c9 differs from pull request most recent head 384f737. Consider uploading reports for the commit 384f737 to get more accurate results

Files	Patch %	Lines
maa-cli/src/installer/maa_core.rs	12.94%	121 Missing ⚠️
maa-cli/src/dirs.rs	27.58%	42 Missing ⚠️
maa-cli/src/installer/maa_cli.rs	32.55%	29 Missing ⚠️
maa-cli/src/main.rs	0.00%	29 Missing ⚠️
maa-cli/src/installer/download.rs	0.00%	16 Missing ⚠️
maa-cli/src/run/mod.rs	0.00%	13 Missing ⚠️
maa-cli/src/installer/version_json.rs	59.09%	9 Missing ⚠️
maa-cli/src/config/cli/maa_cli.rs	73.33%	8 Missing ⚠️
maa-cli/src/installer/extract.rs	0.00%	4 Missing ⚠️
maa-cli/src/config/cli/maa_core.rs	95.23%	2 Missing ⚠️
... and 2 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #106      +/-   ##
==========================================
+ Coverage   25.96%   31.34%   +5.38%     
==========================================
  Files          21       24       +3     
  Lines        1606     1745     +139     
==========================================
+ Hits          417      547     +130     
- Misses       1189     1198       +9     

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