feat(design-data): teach Figma export generator to honor name-mapping overrides (11k.5)

[GarthDB]

Description

Stacked on #1321 (11k.4). Extends build_export_payload (and the internal
process_*/make_variable_action helpers) with an optional overrides: Option<&HashMap<String, String>> parameter — a legacyKey → Figma-name map.
When a token's legacyKey has an override, the generator emits that name
instead of the default {prefix}/{legacyKey}; absent or empty overrides
keep today's 1:1 behavior unchanged for every existing caller.

design-data figma export gains a --mapping <PATH> flag that loads the
override map from a figma audit artifact (reads its nested overrides
field) or a bare {legacyKey: name} JSON object, dropping any empty-string
placeholder entries (the audit's "needs a decision" markers).

Related Issue

spectrum-design-data-11k.5 (bd), depends on spectrum-design-data-11k.4 (#1321)

Motivation and Context

11k.4's audit produces an override scaffold for every naming divergence
between the generator and the real S2–Web file. This closes the loop: once
someone fills in real names for the scaffold's generated_only entries,
figma export --mapping <artifact> will actually emit them, moving the
generator from "1:1 by convention" toward "authoritative for the real file."

How Has This Been Tested?

• New unit test in mapping.rs: one token with an override remaps to the
  override name; a second token with no override still gets the default
  {prefix}/{legacyKey} name.
• All existing mapping.rs tests remain green, unchanged.
• moon run sdk:build && moon run sdk:test && moon run sdk:lint (clippy
  -D warnings) all pass.
• node tools/changeset-linter/src/cli.js check --fail-on-warnings passes.

Screenshots (if appropriate):

N/A — CLI/library change only.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[changeset-bot]

🦋 Changeset detected

Latest commit: 2754ec2

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 10 packages

Name	Type
@adobe/spectrum-design-data	Minor
@adobe/spectrum-component-api-schemas	Patch
@adobe/design-system-registry	Patch
@adobe/design-data-agent-mcp	Patch
@adobe/design-data-mcp	Patch
markdown-generator	Patch
@adobe/token-corpus-migrate	Patch
@adobe/token-naming-audit	Patch
component-options-editor	Patch
@adobe/spectrum-design-data-mcp	Patch

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[github-actions]

🎨 Token Changes Report

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Original Branch: main

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[github-actions]

🧩 Component Schema Changes Report

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[github-actions]

Run report for 2754ec28

Total time: 2m 50s | Comparison time: 3m 8s | Estimated savings: 17.6s (9.3% faster)

	Action	Time	Status	Info
⬛️	SetupProto(0.57.4)	0ms	Skipped
🟩	SyncWorkspace	10.3ms	Passed
🟩	SyncProject(sdk)	0.6ms	Passed
⬛️	SetupToolchain(node:20.17.0)	157.2ms	Skipped
⬛️	SetupToolchain(rust:1.88.0)	246.9ms	Skipped
⬛️	SetupToolchain(pnpm:10.17.1)	120.2ms	Skipped
⬛️	SetupToolchain(javascript)	0ms	Skipped
⬛️	SetupEnvironment(javascript, sdk)	0.6ms	Skipped
🟩	SetupEnvironment(rust, sdk)	137.4ms	Passed
⬛️	InstallDependencies(rust, sdk)	2.6ms	Skipped
🟩	RunTask(sdk:fmt-check)	1.2s	Passed
🟩	InstallDependencies(javascript, sdk)	6.6s	Passed
🟩	RunTask(sdk:codegen-check)	289.7ms	Passed
🟩	RunTask(sdk:lint)	48.2s	Passed
🟩	RunTask(sdk:test)	2m 43s	Passed	SLOW

Changed files

.changeset/figma-mapping-overrides.md
.changeset/figma-name-audit.md
sdk/Cargo.lock
sdk/README.md
sdk/cli/src/main.rs
sdk/core/src/figma/audit.rs
sdk/core/src/figma/mapping.rs
sdk/core/src/figma/mod.rs
sdk/core/tests/fixtures/figma/name-mapping.audit.json