removeSourceFile finds the Sources build phase entry by its comment, so a .mm added by 4.0.0 leaves its entry behind #202

Split out of #200, as suggested there: this is its removeSourceFile half.

Summary

removeSourceFile deletes the file's PBXBuildFile by the file's name, but finds its entry in the Sources build phase by comment: longComment(file), "<name> in <group>", with the group the running version detects for the file's type. An entry commented any other way stays in the build phase, pointing at a PBXBuildFile that no longer exists.

An upgrade is enough to get there. 4.0.0 doesn't map .mm, so it comments a .mm's build file in Resources; master, which maps it since #199, looks for in Sources. So a plugin's .mm that cordova-ios added with 4.0.0 and removes with a release that includes #199 leaves its entry in the Sources build phase. Once #201 lands, the same happens to a .c, .cpp, .cc or .cxx that 4.0.0 added.

Steps to reproduce

1. Download the gist https://gist.github.com/YevheniiKotyrlo/83e2ad5c1e82e506fe82cea69371b9d2 into an empty folder: package.json, which depends on xcode from this repository at 354a163 and on xcode@4.0.0 as xcode-4.0.0, and repro.js.
2. Add the repository's test project beside them and install:

   curl -sSfLO https://raw.githubusercontent.com/apache/cordova-node-xcode/354a1631d0a448531e4cc0aee8ca60c89262d1f1/test/parser/projects/full.pbxproj
   npm install

   npm 12 fetches the git dependency only with --allow-git=root.
3. Run node repro.js full.pbxproj. It adds Plugins/com.example.plugin/Plain.mm with addSourceFile(path, {}) and removes it with removeSourceFile(path), as cordova-ios does for a plugin's <source-file> (install, uninstall): first with master for both, then adding with 4.0.0. It prints the build file and build phase lines each addition wrote, and every line still naming Plain.mm after the removal.

Expected: nothing names Plain.mm after the removal, whichever version added it.

Actual: when 4.0.0 added it, the Sources build phase keeps Plain.mm in Resources, whose uuid is defined nowhere:

== added by master, removed by master
added:   F27FAA5682EF4239A600E77C /* Plain.mm in Sources */ = {isa = PBXBuildFile; fileRef = 72327B084AD0454E92716875 /* Plain.mm */; };
added:   F27FAA5682EF4239A600E77C /* Plain.mm in Sources */,
removed: nothing names Plain.mm
== added by xcode@4.0.0, removed by master
added:   F6903D0DF1184805B24735FB /* Plain.mm in Resources */ = {isa = PBXBuildFile; fileRef = 6B24BFC6BB1E4C748A7A0220 /* Plain.mm */; };
added:   F6903D0DF1184805B24735FB /* Plain.mm in Resources */,
removed: F6903D0DF1184805B24735FB /* Plain.mm in Resources */,    <- F6903D0DF1184805B24735FB is defined nowhere

The uuids are random, so they differ from run to run. Node 26.12.1 on Windows 11; xcode from master at 354a163. What Xcode does with the leftover entry I haven't checked.

Reading

lib/pbxProject.js at 354a163: removeSourceFile calls removeFromPbxBuildFileSection, which deletes every PBXBuildFile whose fileRef_comment is the file's basename and records its uuid on file.uuid, then removeFromPbxSourcesBuildPhase, which splices the first entry whose comment === longComment(file). Matching the entry by the uuid removeFromPbxBuildFileSection just found would remove it whatever its comment says. removeFromPbxResourcesBuildPhase, removeFromPbxFrameworksBuildPhase, removeFromPbxCopyfilesBuildPhase and removeFromPbxEmbedFrameworksBuildPhase match by longComment the same way.