refactor(domain): one owner each for non-empty text schemas and UTF-8 head excerpts (#10569)

Fifteen domain schema files each declared z.string().min(1), eight of them
as boundedTextSchema although it bounds nothing. They now share
nonEmptyTextSchema from src/domain/textSchemas.ts; the one trimming copy in
reconstructionCoverage.ts is renamed trimmedTextSchema.

Three private UTF-8 prefix truncators (gdb recent MI records, rizin
diagnostics, environment replay) and src/process/boundedUtf8Text.ts are
replaced by utf8HeadExcerpt in src/domain/utf8HeadExcerpt.ts, which encodes
only the retained prefix and returns a slice of the source text.

src/application/desktop/DesktopBuildActionLog.ts

@@ -1,6 +1,6 @@
 import type { ComputerAction } from "../../domain/desktop/computerActions.js";
 import type { JsonValue } from "../../domain/jsonValue.js";
-import { boundedUtf8Text } from "../../process/boundedUtf8Text.js";
+import { utf8HeadExcerpt } from "../../domain/utf8HeadExcerpt.js";
 
 /** Bytes the log keeps of each string in an action's arguments, such as type's text. */
 export const LOGGED_TEXT_BYTES = 1024;
@@ -35,7 +35,7 @@ const bounded = (
   redact: Redact,
 ): { readonly value: JsonValue; readonly cut: boolean } => {
   if (typeof value === "string") {
-    const { text, truncated } = boundedUtf8Text(
+    const { text, truncated } = utf8HeadExcerpt(
       redact(value),
       LOGGED_TEXT_BYTES,
     );

src/application/environment/environmentReplay.ts

@@ -19,6 +19,7 @@ import {
   type EnvironmentSource,
   type RecordedExchange,
 } from "./environmentSource.js";
+import { utf8HeadExcerpt } from "../../domain/utf8HeadExcerpt.js";
 
 /** Caller arguments as the MCP tool receives them. */
 export type ReplayArguments = Readonly<Record<string, unknown>>;
@@ -307,13 +308,6 @@ export const selectsRecordedLine = (
   return true;
 };
 
-/** The longest prefix of text whose UTF-8 encoding fits the byte limit, encoding only that prefix. */
-const utf8Prefix = (text: string, maxBytes: number): string => {
-  // encodeInto stops before the first character that does not fit, so `read` ends on a boundary.
-  const { read } = new TextEncoder().encodeInto(text, new Uint8Array(maxBytes));
-  return text.slice(0, read);
-};
-
 /** Base64 characters, in whole groups, whose bytes fit the replay limit. */
 const BASE64_LIMIT_CHARS = Math.floor(REPLAY_BODY_LIMIT_BYTES / 3) * 4;
 
@@ -334,7 +328,7 @@ const replayBody = (exchange: RecordedExchange): ReplayBody => {
         : { body: body.encoded.slice(0, BASE64_LIMIT_CHARS), truncated: true };
     case "cut":
       return {
-        body: utf8Prefix(body.text, REPLAY_BODY_LIMIT_BYTES),
+        body: utf8HeadExcerpt(body.text, REPLAY_BODY_LIMIT_BYTES).text,
         truncated: true,
       };
     case "json":
@@ -380,15 +374,18 @@ export const replayAnswer = (
   exact: boolean,
   { body, truncated }: ReplayBody = replayBody(exchange),
 ): ReplayResult => {
-  const recordedPath = utf8Prefix(exchange.path, REPLAY_METADATA_LIMIT_BYTES);
+  const recordedPath = utf8HeadExcerpt(
+    exchange.path,
+    REPLAY_METADATA_LIMIT_BYTES,
+  ).text;
   const recordedQuery =
     exchange.query === null
       ? null
-      : utf8Prefix(exchange.query, REPLAY_METADATA_LIMIT_BYTES);
+      : utf8HeadExcerpt(exchange.query, REPLAY_METADATA_LIMIT_BYTES).text;
   const contentType =
     exchange.contentType === null
       ? null
-      : utf8Prefix(exchange.contentType, REPLAY_METADATA_LIMIT_BYTES);
+      : utf8HeadExcerpt(exchange.contentType, REPLAY_METADATA_LIMIT_BYTES).text;
   return {
     status: exchange.status,
     content_type: contentType,