Add base file support for general data to preserve potion type values across scrapes (#271)

The scraper was overwriting `potion_types.ts` with an empty array on
each run because `General` had no base-loading mechanism — unlike BP/RP
containers which seed from `src/base/` before scraping.

## Changes

- **New base JSON files** in
`packages/bedrock-vanilla-data/src/base/general/`:
- `potion_types.json` — seeds the known values `["Consume",
"ThrownLingering", "ThrownSplash"]`
- `potion_modifiers.json` — empty placeholder following the same pattern

- **`General.load(folder)`** — new static method on the `General` class
that reads base values from JSON files before scraping populates the
rest

- **`Output.load()`** — updated to call
`General.load(baseFolder/general)` alongside the existing
`edu`/`vanilla` OutputSet loads

- **`loadStringArray(filepath)`** — new helper in `json.ts` for loading
plain string arrays; `loadEnsure<string>` silently wraps string items
into `{ id }` objects (by design for BP/RP data), which is incorrect for
simple string fields on `General`

The flow is now consistent with BP/RP containers: base values are loaded
first, scraped values are merged on top, and `cleanStrings()`
deduplicates before saving.

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packages/bedrock-vanilla-data/src/base/general/potion_modifiers.json

@@ -0,0 +1 @@
+[]

packages/bedrock-vanilla-data/src/base/general/potion_types.json

@@ -0,0 +1 @@
+["Consume", "ThrownLingering", "ThrownSplash"]

tools/vanilla-scraper/src/classes/general.ts

@@ -2,6 +2,7 @@ import * as fs from 'fs';
 import * as path from 'path';
 import { Container as BPContainer } from '../bp/container';
 import { cleanStrings, duplicateWithoutNamespace } from '../static/identifier-extension';
+import { loadStringArray } from '../static/json';
 import { saveArray, saveSingle } from '../static/typescript';
 import { GeneralEntity } from './general-entity';
 import { Output } from './output';
@@ -23,6 +24,16 @@ export class General {
   potionTypes: string[] = [];
   features?: string[];
 
+  /**
+   * Load general base data from a folder
+   */
+  static load(folder: string): General {
+    const out = new General();
+    out.potionModifiers = loadStringArray(path.join(folder, 'potion_modifiers.json'));
+    out.potionTypes = loadStringArray(path.join(folder, 'potion_types.json'));
+    return out;
+  }
+
   /**
    * Scrape from output
    */

tools/vanilla-scraper/src/classes/output.ts

@@ -17,6 +17,7 @@ export class Output {
     const out = new Output();
     out.edu = OutputSet.load(path.join(folder, 'edu'));
     out.vanilla = OutputSet.load(path.join(folder, 'vanilla'));
+    out.general = General.load(path.join(folder, 'general'));
 
     return out;
   }

tools/vanilla-scraper/src/static/json.ts

@@ -48,6 +48,36 @@ export function loadEnsure<T>(filepath: string): T[] {
   return load<T[]>(filepath) ?? ([] as Array<T>);
 }
 
+/**
+ * Load a JSON file containing a string array, returning an empty array if file doesn't exist.
+ * Handles both plain string arrays and arrays of objects with an 'id' or 'name' property.
+ */
+export function loadStringArray(filepath: string): string[] {
+  if (!fs.existsSync(filepath)) {
+    return [];
+  }
+
+  try {
+    const data = fs.readFileSync(filepath, 'utf-8');
+    const cleaned = removeCommentsAndTrailingCommas(data);
+    const result = JSON.parse(cleaned);
+
+    if (!Array.isArray(result)) return [];
+
+    return result.map((item): string => {
+      if (typeof item === 'string') return item;
+      if (typeof item === 'object' && item !== null) {
+        const obj = item as Record<string, unknown>;
+        return (typeof obj.id === 'string' ? obj.id : null) ?? (typeof obj.name === 'string' ? obj.name : null) ?? '';
+      }
+      return '';
+    }).filter((s) => s.length > 0);
+  } catch (ex) {
+    console.error(ex);
+    return [];
+  }
+}
+
 /**
  * Save data to a JSON file
  */