feat: prepare Radixor 3.0.0 with contracted tries and compiled patch commands

Introduce contracted compiled patch tries for faster lookup, make compiled
patch commands the primary runtime path, refresh stemmer benchmarks and
documentation, and restructure the documentation for 3.0.0 onboarding.

BREAKING CHANGE: Radixor 3.0.0 promotes compiled patch-command APIs and
new compiled trie artifacts as the primary runtime integration model.

docs/reduction-semantics.md

@@ -103,6 +103,24 @@ This turns reduction into a canonicalization process:
 
 That is how Radixor eliminates duplicated equivalent subtrees.
 
+## Uniform-subtree contraction
+
+Radixor performs one additional internal reduction before each public reduction mode is applied.
+When all reachable entries below a subtree have the same preferred patch command, the subtree is
+contracted into an accepting leaf for that command.
+
+This optimization is deliberately narrower than the public reduction modes:
+
+- it is based on preferred `get()` behavior,
+- it does not depend on child edge shape once the preferred command is uniform,
+- it removes lookup depth that cannot affect the selected command,
+- it preserves the standard single-result stemming path used by `StemmerPatchTrieLoader.loadCompiled(...)`.
+
+The effect is especially visible in large dictionary tries with many inflected forms that map to
+the same command class, such as no-op preservation or common suffix deletion. Runtime lookup can
+return the accepting leaf as soon as it is reached instead of traversing the remaining characters
+only to discover the same command deeper in the trie.
+
 ## Count aggregation and compiled state
 
 When multiple original build-time subtrees collapse into one canonical reduced node, local counts may be aggregated.