[text-auditor] Fix clear field-description typos in CEF, Memcached, and PostgreSQL text

## Text Improvements

The following user-facing text issues were found in source field descriptions. Each is a low-effort fix and should also correct downstream generated exported-fields docs.

### 1. Misspelling: `sucess` -> `success`

**File:** `x-pack/filebeat/processors/decode_cef/_meta/fields.yml` (line 743)
**Current text:** `description: Outcome of the event (e.g. sucess, failure, or attempt).`
**Suggested fix:** `description: Outcome of the event (e.g. success, failure, or attempt).`
**Why:** Clear typo in user-facing field description.

### 2. Grammar error: `If the SELECT query if successful`

**File:** `packetbeat/protos/pgsql/_meta/fields.yml` (lines 25 and 30)
**Current text:** `If the SELECT query if successful, this field is set to the number`
**Suggested fix:** `If the SELECT query is successful, this field is set to the number`
**Why:** Clear duplicated/incorrect wording in user-facing field descriptions.

### 3. Misspelling: `Numer` -> `Number`

**File:** `metricbeat/module/memcached/stats/_meta/fields.yml` (line 31)
**Current text:** `Numer of successful connect attempts to this server since it has been started.`
**Suggested fix:** `Number of successful connect attempts to this server since it has been started.`
**Why:** Clear typo in user-facing field description.

## Suggested Actions

- [ ] Update `x-pack/filebeat/processors/decode_cef/_meta/fields.yml` line 743 (`sucess` -> `success`).
- [ ] Update both affected lines in `packetbeat/protos/pgsql/_meta/fields.yml` (`query if successful` -> `query is successful`).
- [ ] Update `metricbeat/module/memcached/stats/_meta/fields.yml` line 31 (`Numer` -> `Number`).
- [ ] Regenerate any exported/reference docs that derive from these `_meta/fields.yml` sources so generated text stays consistent.

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> - [x] expires on Aug 24, 2026, 1:28 PM UTC

Start with the three named source files: x-pack/filebeat/processors/decode_cef/_meta/fields.yml, packetbeat/protos/pgsql/_meta/fields.yml, and metricbeat/module/memcached/stats/_meta/fields.yml. Correct the specified typos and grammar in the field descriptions, then regenerate any exported or reference documentation derived from these files and verify the corrected text is consistent.

Written by the indexing model from the issue text.