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: 208 lines in your changes are missing coverage. Please review.

Comparison is base (c915139) 25.96% compared to head (577af96) 40.79%.

Files	Patch %	Lines
maa-cli/src/installer/maa_core.rs	12.94%	121 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	46.15%	7 Missing ⚠️
maa-cli/src/installer/extract.rs	0.00%	4 Missing ⚠️
maa-cli/src/run/fight.rs	0.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #118       +/-   ##
===========================================
+ Coverage   25.96%   40.79%   +14.83%     
===========================================
  Files          21       24        +3     
  Lines        1606     1733      +127     
===========================================
+ Hits          417      707      +290     
+ Misses       1189     1026      -163     

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