Add full latency grid (mean/p50/p90/p99 × TTFT/TPOT/E2E) as f6 companion

The headline f6_e2e_latency_bars only shows p90, hiding three regimes:
  - mean: unified dominates (3.3s TTFT, 7.0s E2E vs sticky 5.6s / 12.1s)
  - p50: sticky and unified are tied on first-turn TTFT (0.5s each) —
    sticky's first turn of each session is free, after which queues
    accumulate. Unified beats sticky everywhere else.
  - p99: tail amplification reveals unified's biggest gap —
    TTFT 42.3s vs sticky 74.1s; E2E 68.8s vs sticky 139.7s.

The 12-panel figure is the honest full picture; the 3-panel headline
stays for slide-friendly summary.

- analysis/characterization/window_1_results/raw_stats/{policy}.json:
  cached ttft/tpot/e2e {mean,p50,p90,p99} pulled from dash0
  /home/admin/cpfs/wjh/agentic-kv/outputs/b3_sweep_20260525_095043/
  (b3_policy_comparison.json doesn't record mean, only percentiles).
- analysis/characterization/render_window1_figures.py:
  new fig_b3_latency_full_grid renders the 4×3 grid from the cache.
- figs/f6_e2e_latency_full_grid.png: 12-panel companion.
- PAPER_OUTLINE.md §5.2: both figures embedded; main table column
  renamed from "Hotspot idx" to "Worker p90 (median / max)" to match
  the new metric convention.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

analysis/characterization/window_1_results/raw_stats/lmetric.json

@@ -0,0 +1,23 @@
+{
+  "ttft": {
+    "count": 1214.0,
+    "mean": 5.111546324698484,
+    "p50": 0.9387824369769078,
+    "p90": 15.671339168207492,
+    "p99": 53.56683189840049
+  },
+  "tpot": {
+    "count": 1214.0,
+    "mean": 0.01757124870168204,
+    "p50": 0.008854518407308914,
+    "p90": 0.02122720699121469,
+    "p99": 0.18280341184277568
+  },
+  "e2e": {
+    "count": 1214.0,
+    "mean": 9.518126648903337,
+    "p50": 2.754255389008904,
+    "p90": 24.8209177934099,
+    "p99": 80.59924928059091
+  }
+}

analysis/characterization/window_1_results/raw_stats/load_only.json

@@ -0,0 +1,23 @@
+{
+  "ttft": {
+    "count": 1214.0,
+    "mean": 6.268620166597892,
+    "p50": 1.2609447415161412,
+    "p90": 20.197147866390882,
+    "p99": 52.84285237012196
+  },
+  "tpot": {
+    "count": 1214.0,
+    "mean": 0.02406975794215626,
+    "p50": 0.009231464695980247,
+    "p90": 0.026851662550158716,
+    "p99": 0.3211630676943426
+  },
+  "e2e": {
+    "count": 1214.0,
+    "mean": 11.702793988628443,
+    "p50": 3.58568156149704,
+    "p90": 33.459180271782685,
+    "p99": 93.95083751494239
+  }
+}

analysis/characterization/window_1_results/raw_stats/sticky.json

@@ -0,0 +1,23 @@
+{
+  "ttft": {
+    "count": 1214.0,
+    "mean": 5.55315460854824,
+    "p50": 0.5415176274836995,
+    "p90": 18.021296651283045,
+    "p99": 74.09429564891524
+  },
+  "tpot": {
+    "count": 1214.0,
+    "mean": 0.027834537397398284,
+    "p50": 0.008952101894096181,
+    "p90": 0.03641285916619554,
+    "p99": 0.35152006935195085
+  },
+  "e2e": {
+    "count": 1214.0,
+    "mean": 12.109200157184377,
+    "p50": 2.081947358994512,
+    "p90": 34.62592205510591,
+    "p99": 139.68334607904353
+  }
+}

analysis/characterization/window_1_results/raw_stats/unified.json

@@ -0,0 +1,23 @@
+{
+  "ttft": {
+    "count": 1213.0,
+    "mean": 3.2790960856202394,
+    "p50": 0.4997710260213353,
+    "p90": 7.345769894809922,
+    "p99": 42.34170345296613
+  },
+  "tpot": {
+    "count": 1213.0,
+    "mean": 0.012493800538265787,
+    "p50": 0.008079791456705824,
+    "p90": 0.017110194704198407,
+    "p99": 0.12655874612209597
+  },
+  "e2e": {
+    "count": 1213.0,
+    "mean": 6.961301470549104,
+    "p50": 1.7495028690318577,
+    "p90": 18.033410895219994,
+    "p99": 68.80023987947489
+  }
+}