fix: keyword matching with non-word boundary characters

Keywords starting/ending with non-word characters (brackets, parens,
dashes) never matched because \b requires a word↔non-word transition.
Now uses smart boundaries: \b for word-char edges, (?<=\s|^)/(?=\s|$)
for non-word edges. Also pre-compiles regex patterns once per batch
instead of recreating them for every description × keyword combination.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/services/categorizationService.ts

@@ -16,11 +16,66 @@ function normalizeDescription(desc: string): string {
     .trim();
 }
 
+const WORD_CHAR = /\w/;
+
+/**
+ * Build a regex pattern for a keyword with smart boundaries.
+ * Uses \b when the keyword edge is a word character (a-z, 0-9, _),
+ * and uses (?<=\s|^) / (?=\s|$) when the edge is a non-word character
+ * (e.g., brackets, parentheses, dashes). This ensures keywords like
+ * "[VIREMENT]" or "(INTERAC)" can match correctly.
+ */
+function buildKeywordRegex(normalizedKeyword: string): RegExp {
+  const escaped = normalizedKeyword.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
+  const left = WORD_CHAR.test(normalizedKeyword[0])
+    ? "\\b"
+    : "(?<=\\s|^)";
+  const right = WORD_CHAR.test(normalizedKeyword[normalizedKeyword.length - 1])
+    ? "\\b"
+    : "(?=\\s|$)";
+  return new RegExp(`${left}${escaped}${right}`);
+}
+
 interface CategorizationResult {
   category_id: number | null;
   supplier_id: number | null;
 }
 
+interface CompiledKeyword {
+  regex: RegExp;
+  category_id: number;
+  supplier_id: number | null;
+}
+
+/**
+ * Compile keywords into regex patterns once for reuse across multiple matches.
+ */
+function compileKeywords(keywords: Keyword[]): CompiledKeyword[] {
+  return keywords.map((kw) => ({
+    regex: buildKeywordRegex(normalizeDescription(kw.keyword)),
+    category_id: kw.category_id,
+    supplier_id: kw.supplier_id ?? null,
+  }));
+}
+
+/**
+ * Match a normalized description against compiled keywords.
+ */
+function matchDescription(
+  normalized: string,
+  compiled: CompiledKeyword[]
+): CategorizationResult {
+  for (const kw of compiled) {
+    if (kw.regex.test(normalized)) {
+      return {
+        category_id: kw.category_id,
+        supplier_id: kw.supplier_id,
+      };
+    }
+  }
+  return { category_id: null, supplier_id: null };
+}
+
 /**
  * Auto-categorize a single transaction description.
  * Returns matching category_id and supplier_id, or nulls if no match.
@@ -33,20 +88,9 @@ export async function categorizeDescription(
     "SELECT * FROM keywords WHERE is_active = 1 ORDER BY priority DESC"
   );
 
+  const compiled = compileKeywords(keywords);
   const normalized = normalizeDescription(description);
-
-  for (const kw of keywords) {
-    const normalizedKeyword = normalizeDescription(kw.keyword);
-    const escaped = normalizedKeyword.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
-    if (new RegExp(`\\b${escaped}\\b`).test(normalized)) {
-      return {
-        category_id: kw.category_id,
-        supplier_id: kw.supplier_id ?? null,
-      };
-    }
-  }
-
-  return { category_id: null, supplier_id: null };
+  return matchDescription(normalized, compiled);
 }
 
 /**
@@ -61,18 +105,10 @@ export async function categorizeBatch(
     "SELECT * FROM keywords WHERE is_active = 1 ORDER BY priority DESC"
   );
 
+  const compiled = compileKeywords(keywords);
+
   return descriptions.map((desc) => {
     const normalized = normalizeDescription(desc);
-    for (const kw of keywords) {
-      const normalizedKeyword = normalizeDescription(kw.keyword);
-      const escaped = normalizedKeyword.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
-      if (new RegExp(`\\b${escaped}\\b`).test(normalized)) {
-        return {
-          category_id: kw.category_id,
-          supplier_id: kw.supplier_id ?? null,
-        };
-      }
-    }
-    return { category_id: null, supplier_id: null };
+    return matchDescription(normalized, compiled);
   });
 }