Merge remote-tracking branch 'origin/token-meter-service' into compact-post-step-overflow-recovery

# Conflicts:
#	docs/core-data-structures/compaction.md
#	docs/rfc/implemented/architecture/2026-07-15-replay-token-meter-service.i18n.yaml
#	docs/rfc/implemented/architecture/2026-07-15-replay-token-meter-service.md
#	docs/rfc/implemented/architecture/2026-07-15-replay-token-meter-service.zh.md
#	docs/rfc/implemented/feature/2026-06-18-compaction-capability-seam.md
#	examples/coding-agent/cordis.yml
#	packages/compact/compact-basic/README.md
#	packages/compact/compact-basic/src/automatic.ts
#	packages/compact/compact-basic/src/config.ts
#	packages/compact/compact-basic/src/index.ts
#	packages/compact/compact-basic/tests/compact-basic.spec.ts

docs/core-data-structures/compaction.md

@@ -56,7 +56,7 @@ Automatic callers state why policy is running; implementations may treat confirm
 export type CompactionTrigger = 'pressure' | 'context-overflow'
 ```
 
-`CompactService` exposes `compactIfNeeded(agent, trigger, signal)` for automatic `pressure` or `context-overflow` policy, returning `null` when no safe work exists, and `compactRegion(...)` for an explicit inclusive surface range. Implementations must forward the supplied signal to summarization. The seam owns no pricing API: `dsh-compact-basic` resolves the durable routed model through [`ctx.tokenMeter`](token-meter.md), whose model-bound handle owns estimation and replay, while the backend owns retention, event sequencing, and summarization.
+`CompactService` exposes `compactIfNeeded(agent, trigger, signal)` for automatic `pressure` or `context-overflow` policy, returning `null` when no safe work exists, and `compactRegion(...)` for an explicit inclusive surface range. Implementations must forward the supplied signal to summarization. The seam owns no pricing API: the singleton [`ctx.tokenMeter`](token-meter.md) directly owns estimation and replay, while `dsh-compact-basic` owns retention, event sequencing, routed summarization calls, and their configuration.
 
 Pressure compaction runs at serial `agent/post-step`, after successful assistant output, tool results, buffered context, and steering are durable but before `step/end`. Failed-request recovery runs through `agent/request-error` after the failed step closes, and authorizes a fresh numbered-step retry only when the surface replacement generation advances. Region boundaries preserve tool-call/result pairing but do not preserve whole turns, allowing early closed steps of one oversized turn to compact. `dsh-compact-basic` owns thresholds, retained-tail policy, overflow caps, and failure handling.
 

docs/core-data-structures/session.md

@@ -200,7 +200,7 @@ export interface SurfaceNode {
 }
 ```
 
-`SurfaceNode` is positional state, not durable identity. A replacement can remove a caller-retained node or make a copied `next` stale; consumers that cross a surface mutation validate membership and resolve successors from `Session.surface.nodes`. `SurfaceManager.replaceGeneration` increments for each replacement so incremental consumers can distinguish pure tail growth from a rewrite.
+`SurfaceNode` is positional state, not durable identity. A replacement can remove a caller-retained node or make a copied `next` stale; consumers that cross a surface mutation validate membership and answer positional queries from `Session.surface.nodes`. `SurfaceManager.replaceGeneration` increments for each replacement so incremental consumers can distinguish pure tail growth from a rewrite.
 
 ### `SurfaceFoldReplacement` and `SurfaceFoldResult` — a complete surface replay
 

docs/core-data-structures/token-meter.md

@@ -1,6 +1,6 @@
 # Token Meter
 
-`@deepseek-ai/dsh-token-meter` exposes detached replay measurements for request pressure and positional surface pricing. Scalar and surface snapshots carry the number of durable events consumed as `logRevision`; consumers compare revisions before making a joint decision.
+`@deepseek-ai/dsh-token-meter` exposes one detached replay snapshot for request pressure and positional surface pricing. `logRevision` is the number of durable events consumed for every field in the measurement.
 
 Source: [`packages/llm/token-meter/src/types.ts`](../../packages/llm/token-meter/src/types.ts)
 
@@ -8,8 +8,6 @@ Source: [`packages/llm/token-meter/src/types.ts`](../../packages/llm/token-meter
 
 ```ts type-equiv
 interface TokenMeasurement {
-  /** Model profile used for every heuristic component. */
-  readonly model: string
   /** Number of durable events consumed; equal to the next unread event seq. */
   readonly logRevision: number
   /** Provider or heuristic anchor used for this measurement. */
@@ -18,10 +16,14 @@ interface TokenMeasurement {
   readonly surfaceDeltaTokens: number
   /** Non-negative current request-and-response pressure. */
   readonly totalTokens: number
+  /** Total heuristic tokens across the current surface. */
+  readonly surfaceTokens: number
+  /** Current surface nodes in positional head-to-tail order. */
+  readonly nodes: readonly TokenSurfaceNode[]
 }
 ```
 
-`baseline.kind === 'usage'` means a successful provider call has the same model and canonical envelope. `estimated` means the meter repriced the complete envelope and surface. Signed `surfaceDeltaTokens` preserves growth and shrinkage relative to a matching provider or estimated anchor.
+`baseline.kind === 'usage'` means the latest successful provider call has the same canonical request envelope and its total is no lower than that call's full heuristic anchor. `estimated` means no reusable conservative usage anchor exists, so the service priced the complete envelope and surface with its fixed heuristic. A later successful request replaces the earlier anchor; signed `surfaceDeltaTokens` preserves growth and shrinkage relative to a matching anchor. `totalTokens` remains request-and-response pressure, while `surfaceTokens` is the surface-only heuristic total and equals the sum of the node prices.
 
 ## `TokenSurfaceNode`
 
@@ -34,19 +36,4 @@ interface TokenSurfaceNode {
 }
 ```
 
-## `TokenSurfaceMeasurement`
-
-```ts type-equiv
-interface TokenSurfaceMeasurement {
-  /** Model profile used to price every node. */
-  readonly model: string
-  /** Number of durable events consumed; equal to the next unread event seq. */
-  readonly logRevision: number
-  /** Total heuristic tokens across the current surface. */
-  readonly totalTokens: number
-  /** Current surface nodes in positional head-to-tail order. */
-  readonly nodes: readonly TokenSurfaceNode[]
-}
-```
-
 Surface order is authoritative; replacement nodes can have higher durable seqs than later positional nodes. The snapshot is immutable and does not grow when the underlying replay fold advances.