fix(rest-api): handle mixed bare filters and conjunctions in filter parser

https://sonarly.com/issue/32412?type=bug

The REST API filter parser's `addDefaultConjunctionIfMissing` function uses a naive heuristic — checking for the presence of any parentheses — to decide whether to wrap the filter in a default `and()` conjunction. When a filter mixes bare conditions with explicit conjunctions (e.g., `status[eq]:'TODO',and(title[ilike]:'%test%')`), the parentheses from the nested conjunction trick the function into thinking a root conjunction already exists, causing the entire filter string to be parsed as a single base filter and producing a 400 error.

Fix: **What changed:** Replaced the naive parentheses-presence heuristic in `addDefaultConjunctionIfMissing` with the same regex pattern used by `parseFilter` to detect a root-level conjunction.

**Before:** The function checked `filterQuery.includes('(') && filterQuery.includes(')')`. If the filter contained *any* parentheses (e.g. from a nested `and(...)` or `or(...)`), it assumed a root conjunction already existed and returned the input unchanged. This meant `status[eq]:'TODO',and(title[ilike]:'%test%')` was NOT wrapped, causing a parse failure downstream.

**After:** The function checks `^(or|and|not)\((.+)\)$` — the exact same regex `parseFilter` uses to detect a root conjunction. This correctly identifies that `status[eq]:'TODO',and(title[ilike]:'%test%')` does NOT start with a root conjunction and wraps it in `and(...)`.

**Files changed:**
1. `add-default-conjunction.util.ts` — Replaced `includes('(')` check with `ROOT_CONJUNCTION_REGEX.test()` using the same regex pattern as `parseFilter`.
2. `__tests__/add-default-conjunction.util.spec.ts` — Added 5 test cases covering: mixed bare filters with nested conjunctions (the reported bug), `or` and `not` root conjunctions, and multiple bare filters without parentheses.

packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/__tests__/add-default-conjunction.util.spec.ts

@@ -12,4 +12,38 @@ describe('addDefaultConjunctionIfMissing', () => {
       'and(field[eq]:1)',
     );
   });
+
+  it('should add default conjunction when bare filters are mixed with nested conjunctions', () => {
+    expect(
+      addDefaultConjunctionIfMissing(
+        "status[eq]:'TODO',and(title[ilike]:'%test%')",
+      ),
+    ).toEqual("and(status[eq]:'TODO',and(title[ilike]:'%test%'))");
+  });
+
+  it('should add default conjunction for multiple bare filters with nested or', () => {
+    expect(
+      addDefaultConjunctionIfMissing(
+        "field1[in]:['a','b'],or(field2[like]:'%x%')",
+      ),
+    ).toEqual("and(field1[in]:['a','b'],or(field2[like]:'%x%'))");
+  });
+
+  it('should not add default conjunction for or root conjunction', () => {
+    expect(
+      addDefaultConjunctionIfMissing('or(field[eq]:1,field[eq]:2)'),
+    ).toEqual('or(field[eq]:1,field[eq]:2)');
+  });
+
+  it('should not add default conjunction for not root conjunction', () => {
+    expect(addDefaultConjunctionIfMissing('not(field[eq]:1)')).toEqual(
+      'not(field[eq]:1)',
+    );
+  });
+
+  it('should add default conjunction for multiple bare filters', () => {
+    expect(
+      addDefaultConjunctionIfMissing('field1[eq]:1,field2[gte]:10'),
+    ).toEqual('and(field1[eq]:1,field2[gte]:10)');
+  });
 });

packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/add-default-conjunction.util.ts

@@ -2,8 +2,12 @@ import { Conjunctions } from 'src/engine/api/rest/input-request-parsers/filter-p
 
 export const DEFAULT_CONJUNCTION = Conjunctions.and;
 
+const ROOT_CONJUNCTION_REGEX = new RegExp(
+  `^(${Object.values(Conjunctions).join('|')})\\((.+)\\)$`,
+);
+
 export const addDefaultConjunctionIfMissing = (filterQuery: string): string => {
-  if (!(filterQuery.includes('(') && filterQuery.includes(')'))) {
+  if (!ROOT_CONJUNCTION_REGEX.test(filterQuery)) {
     return `${DEFAULT_CONJUNCTION}(${filterQuery})`;
   }