(core) make AccessRules and FullCopies effective

Summary:
This allows `*SPECIAL:AccessRules` to give read access to the access rules to more users, and `*SPECIAL:FullCopies` to grant download/copy rights to more users.

This diff also changes forks to be owned by the user who forked them (previously they were an editor), since that feels more natural.

Test Plan: Added and updated tests.

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D2760

app/common/ACLRuleCollection.ts

@@ -44,8 +44,8 @@ const SPECIAL_RULE_SETS: Record<string, RuleSet> = {
     }, {
       aclFormula: "",
       matchFunc: defaultMatchFunc,
-      permissions: parsePermissions('none'),
-      permissionsText: 'none',
+      permissions: parsePermissions('-R'),
+      permissionsText: '-R',
     }],
   },
   FullCopies: {
@@ -59,8 +59,8 @@ const SPECIAL_RULE_SETS: Record<string, RuleSet> = {
     }, {
       aclFormula: "",
       matchFunc: defaultMatchFunc,
-      permissions: parsePermissions('none'),
-      permissionsText: 'none',
+      permissions: parsePermissions('-R'),
+      permissionsText: '-R',
     }],
   }
 };
@@ -100,6 +100,9 @@ export class ACLRuleCollection {
   // Maps 'tableId:colId' to one of the RuleSets in the list _columnRuleSets.get(tableId).
   private _tableColumnMap = new Map<string, RuleSet>();
 
+  // Rules for SPECIAL_RULES_TABLE_ID "columns".
+  private _specialRuleSets = new Map<string, RuleSet>();
+
   // Map of tableId to the single default RuleSet for the table (colIds of '*')
   private _tableRuleSets = new Map<string, RuleSet>();
 
@@ -119,6 +122,7 @@ export class ACLRuleCollection {
 
   // Return the RuleSet for "tableId:colId", or undefined if there isn't one for this column.
   public getColumnRuleSet(tableId: string, colId: string): RuleSet|undefined {
+    if (tableId === SPECIAL_RULES_TABLE_ID) { return this._specialRuleSets.get(colId); }
     return this._tableColumnMap.get(`${tableId}:${colId}`);
   }
 
@@ -220,6 +224,7 @@ export class ACLRuleCollection {
     this._defaultRuleSet = defaultRuleSet;
     this._tableIds = [...tableIds];
     this._userAttributeRules = userAttributeMap;
+    this._specialRuleSets = specialRuleSets;
   }
 
   /**