[eas-cli][eas-json] use node18 as tsconfig base

[quinlanj]

Why

Followup from #2736 (comment)

Standardize TypeScript configuration across packages by adopting the recommended Node.js 18 TypeScript configuration. This helps ensure consistent TypeScript settings and reduces configuration duplication.

How

• Added @tsconfig/node18 dependency to eas-cli and eas-json packages
• Extended the base Node 18 TypeScript configuration in both packages
• Removed redundant compiler options that are already included in the Node 18 preset
• Updated module resolution strategy to explicitly use "node"

Test Plan

Current tests pass

[quinlanj]

• [eas-cli][eas-json] use node18 as tsconfig base #2739 👈 (View in Graphite)
• main

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[github-actions]

❌ It looks like a changelog entry is missing for this PR. Add it manually to CHANGELOG.md.
⏩ If this PR doesn't require a changelog entry, such as if it's an internal change that doesn't affect the user experience, you can add the "no changelog" label to the PR.

[github-actions]

Size Change: -17.2 kB (-0.03%)

Total Size: 52.6 MB

Filename	Size	Change
./packages/eas-cli/dist/eas-linux-x64.tar.gz	52.6 MB	-17.2 kB (-0.03%)

_{compressed-size-action}

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 52.73%. Comparing base (868fd39) to head (00e73c5).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2739   +/-   ##
=======================================
  Coverage   52.73%   52.73%           
=======================================
  Files         580      580           
  Lines       22280    22280           
  Branches     4358     4358           
=======================================
  Hits        11747    11747           
  Misses      10498    10498           
  Partials       35       35           

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[github-actions]

Subscribed to pull request

File Patterns	Mentions
**/*	@szdziedzic, @khamilowicz, @sjchmiela
packages/eas-json/**	@szdziedzic, @khamilowicz, @sjchmiela

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[szdziedzic]

looks reasonable (after merge conflicts are resolved and tests stop failing)