docs(paged): consolidate the dev-trail docs into one canonical README

The paged-attention patch directory had accumulated ~55 scattered dev docs
(results, progress, scope, lever, and gap-analysis notes). Consolidate the
durable content of all of them into one canonical
backend/cpp/llama-cpp/patches/paged/README.md covering: what the patchset is,
the architecture (paged KV + block-table flash-attn, the gated-DeltaNet SSM
decode path, NVFP4 FP4-MMA, the decode-first scheduler), the full 0001-0030
patch series table with bit-exact status, the GB10 benchmarks
(patched-vs-stock-vs-vLLM + the Apple M4 architectural note), the dev notes
(bit-exact methodology, the per-path gate, the MoE-parity conclusion, the
rejected/flat levers, the opt-in bf16-SSM mode), arch+quant generality, the
pin + canary maintenance policy, and the published NVFP4 gallery models.

Delete the consolidated-away dev trail. Keep the three operational docs the
README links to: PIN_SYNC_c299a92c.md (canary reference), PAGED_BITEXACT_NOTE.md
(per-path gate reference) and LOCALAI_LLAMACPP_BACKEND_PLAN.md (the
ship-as-own-backend design-of-record), plus the benchmark plots + csv. The
.patch files and the unit/bench .cpp are untouched.

Repoint every external reference to a deleted doc at the new README:
grpc-server.cpp, docs/content/features/backends.md, gallery/index.yaml, the
canary apply script (PIN_BUMP_APPLY_CHECK.md -> README), and the base
patches/README.md (ADDITIVE_DESIGN.md -> README). The canary's PIN_SYNC
reference still resolves; its inert SSM_DECODE_FIX_RESULTS.md glob (a
patch-internal path matcher, not a repo-doc link) is left intact.

Assisted-by: Claude:opus-4.8 [Claude Code]
Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

backend/cpp/llama-cpp/grpc-server.cpp

@@ -850,7 +850,7 @@ static void params_parse(server_context& /*ctx_server*/, const backend::ModelOpt
         // common_context_params_to_llama (patch 0026) only when the --ssm-bf16-tau CLI flag is unset.
         // Unset / non-positive => env untouched, so stock stays byte-identical and bit-exact (an
         // externally exported LLAMA_SSM_BF16_TAU still works as an escape hatch). NOTE: this mode is
-        // NOT bit-exact (~91% same-top-p ceiling); see patches/paged/A_HYBRID_SSM_RESULTS.md.
+        // NOT bit-exact (~91% same-top-p ceiling); see patches/paged/README.md (Dev notes).
         } else if (!strcmp(optname, "ssm_bf16_tau") || !strcmp(optname, "ssm_hybrid_tau")) {
             if (optval != NULL) {
                 try {