fix: preserve provider ancestry during hydration recovery (#40)

* fix: preserve provider ancestry during hydration recovery

* fix: retain the document shell when hydration recovery fails

Author: tannerlinsley

.changeset/hydration-provider-ancestry.md

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+---
+'@tanstack/redact': patch
+---
+
+Keep component and context provider ancestry when recovering from a hydration mismatch. Document recovery preserves the existing shell, root renders still update the full app, and abandoned effects are cleaned up.

benchmarks/HYDRATION_RECOVERY.md

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+# Hydration recovery size review
+
+Document mismatch recovery keeps the original component and provider tree.
+The recovery target selector now handles local hosts, the document body and
+root fallback in one place. No feature is disabled or generated bundle patched.
+
+Production es2022 ESM builds use the existing `measureSizes` command with
+esbuild 0.28.0 and Node 24.15.0. These are entry bundles retaining all exports,
+not a whole-site size comparison or a runtime performance result.
+
+The baseline is unmodified revision `62b81c1c6e0aa38e06ad70bc72d650f739730314`,
+extracted and built in `/private/tmp/redact-size-baseline-Cdgx1m/package`.
+The corrected package is `/private/tmp/redact-hydration-reviewed-f0677f5/package`.
+The generated baseline and recovery records in `results/` bind every measured
+source and built module, the compiler version and the exact entry sizes.
+
+| Built entry | Baseline gzip bytes | Recovery gzip bytes | Change |
+| --- | ---: | ---: | ---: |
+| DOM API | 25,216 | 25,252 | +36 |
+| DOM client | 24,960 | 24,894 | -66 |
+| Combined client | 28,125 | 28,061 | -64 |
+| Combined client, default Vite | 23,290 | 23,227 | -63 |
+
+The original DOM budget is 25,246 bytes. The corrected entry exceeds it by
+6 bytes. The approved budget remains 25,282, leaving a 30-byte margin.
+Only this entry's budget changes, all other limits stay intact.
+This is an explicit acceptance of the measured correctness cost, not a pass
+under the old limit. The combined client becomes smaller, not larger.
+
+PR review also caught cleanup targeting the entire document when a narrowed
+recovery retry throws. Cleanup now retains the same narrowed target. Its new
+regression fails before the fix and passes afterward, preserving the document
+shell and head resources. Both reset calls now pass an explicit target, so the
+unused default parameter is removed. This reduces the approved candidate by
+5 gzip bytes for the DOM API and 3 for the combined client, without adding work
+to the render path.
+
+Compression does not move uniformly. Compared with the approved candidate,
+minified sizes are unchanged, while the built DOM entry adds 39 Brotli bytes.
+Against the original baseline, that entry is +44 minified, +36 gzip and
++72 Brotli bytes. DOM client, combined client and default-Vite combined client
+remain smaller in all three formats. The JSON records include every feature
+variant, including Brotli increases in some variants. No additional budget
+increase is made for the review fix.
+
+The earlier recovery repair and its failed size checks remain recorded in
+the Container report `reports/redact-hydration-repair-2026-10-04.md`.
+The new size budget does not waive hydration, context, event, state, cleanup,
+type checking, build verification or the strict three-engine real-site checks.