fix(cli): preserve example JSON key order in ledger publish

[devin-ai-integration]

Description

Fixes ledger publish reordering API example JSON fields alphabetically.

Changes Made

The CLI's publishDocsLedger.ts uses stableStringify to serialize the API manifest blob — this recursively sorts ALL object keys at every nesting level for deterministic hashing, including preformatted API example bodies (requestBody/responseBody).

Before (broken): example { "name": "Monstera", "species": "...", "id": "..." } → { "id": "...", "name": "Monstera", "species": "..." }

After (fixed): example key order preserved as authored.

The fix teaches stableStringify to skip sorting for subtrees rooted at known preformatted keys:

const PREFORMATTED_KEYS = new Set(["requestBody", "responseBody", "payload", "body"]);

function stableStringify(value: unknown): string {
    const preformatted = new WeakSet();
    return JSON.stringify(value, function (key, val) {
        if (PREFORMATTED_KEYS.has(key) && val != null && typeof val === "object") {
            preformatted.add(val);
            return val; // skip sorting for this subtree root
        }
        // propagate the mark to child objects via `this` (parent holder)
        if (this != null && typeof this === "object" && preformatted.has(this)) {
            if (val != null && typeof val === "object") preformatted.add(val);
            return val;
        }
        // sort structural keys for determinism
        if (val != null && typeof val === "object" && !Array.isArray(val)) {
            return Object.fromEntries(Object.entries(val).sort(...));
        }
        return val;
    });
}

Uses a WeakSet to track which objects belong to a preformatted subtree so deeply nested keys (e.g. care.water inside a responseBody) are also preserved. CLI-only change — no FDR changes needed.

Preformatted keys cover all z.unknown() example body fields in the fdr-sdk register contract:

• Endpoint examples: requestBody, responseBody

• Webhook examples: payload

• WebSocket message examples: body

• Added changelog entry

Testing

• Unit test added — endpoint with responseBody whose keys are intentionally non-alphabetical; verifies both top-level and nested key order preserved
• Existing determinism test (Map insertion order stability) continues to pass
• All 207 tests in @fern-api/remote-workspace-runner pass

Link to Devin session: https://app.devin.ai/sessions/b5df68c7e9ef4f629ca01c7a1f0aac15
Requested by: @broady

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✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.