Build a project's TcGlobals with its own path map when the framework imports are cached

[xperiandri]

Fixes #20474

FrameworkImportsCache caches the framework TcImports together with the TcGlobals built for the first project of a framework set, and its key does not include the path map. A project reusing the entry got a new TcGlobals only when langVersion or realsig differed, and copied pathMap from the cached instance even then. TypedTreePickle.p_range applies that map to every range it writes and EncodeSignatureData to compileTimeWorkingDir, so the in-memory reference data a project exposes to its consumers was mapped with the --pathmap of whichever project filled the cache first: a project without a map lent mapped, relative file names to its consumers, and a project with a map lost it when a sibling came first.

Seen in Visual Studio on a solution with <PathMap> in Directory.Build.props: symbols imported from a sibling project carried a doubled, relative file name and Go To Definition opened the generated signature.

pathMap now takes part in the decision to rebuild TcGlobals, like langVersion and realsig, and the new instance takes it from the project's own TcConfig. The cached framework imports do not depend on the map, so the key is unchanged.

#20470 keeps the IDE from passing --pathmap at all; this makes the cache correct for any host that checks mapped and unmapped projects with one FSharpChecker.

🤖 Generated with Claude Code

[github-actions]

❗ Release notes required

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@xperiandri,

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Change path	Release notes path	Description
`src/Compiler`	docs/release-notes/.FSharp.Compiler.Service/11.0.200.md	No release notes found or release notes format is not correct

[T-Gro]

🤖🕵️ Approved; CI is still running.

[T-Gro]

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[github-actions]

🔍 Tooling Safety Check — Affects-Design-Time
Affects-Design-Time: Compiler service or Visual Studio behavior changed.

Generated by PR Tooling Safety Check · gpt56 1.9M · ◷

[Copilot]

Copilot review overview

🔵 Needs a closer look

Add coverage for a mapped project after an unmapped sibling populates the cache.

Review effort: Lite
Findings: None

What changed in this PR

Fixes framework import cache reuse so each project’s TcGlobals retains its own path map.

Changes:

• Rebuilds TcGlobals when pathMap differs.
• Applies project-specific path maps in both compiler paths.
• Adds regression coverage and release notes.

File	Summary
tests/​FSharp.Compiler.ComponentTests/​FSharpChecker/​PathMap.fs	Adds path-map cache regression tests.
tests/​FSharp.Compiler.ComponentTests/​FSharp.Compiler.ComponentTests.fsproj	Includes the new test file.
src/​Compiler/​Service/​TransparentCompiler.fs	Applies project-specific path maps.
src/​Compiler/​Service/​IncrementalBuild.fs	Handles path-map differences in cached globals.
docs/​release-notes/​.FSharp.Compiler.Service/​11.0.100.md	Documents the fix.

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