feat(trust): full Duniter web-of-trust membership (params + referents)

Slice 4 of Block 2. The pure rule was already parameterised; this adds the
policy, cold-start and UI around it.

- commons_core: WotParams (sigQty/stepMax/sigValidity, Duniter defaults) +
  WebOfTrust.membersWith; npubToHex helper (NIP-19 decode) for adding roots.
- WotSettings (keystore): the active parameters, configurable — a young
  network loosens them and tightens as it grows, as Ğ1 did. Defaults Duniter.
- TrustReferents: the bootstrap 'seeds' membership is measured from — a
  bundled asset (empty until real founders are curated, no invented keys)
  unioned with referents the user adds by npub/QR. Honest cold-start.
- TrustCubit: computes the full membership verdict against referents+params
  alongside the personal circle, and exposes a TrustTier (networkMember >
  inYourCircle > vouched > unknown). Certifications issued with the active
  validity (they expire and renew, Duniter rule).
- UI: chat trust badge by tier; a 'Network of trust' screen (manage roots +
  advanced params) reached from the profile. i18n en/es/pt/ast.

Tests: WotParams/membersWith, npubToHex, TrustReferents, WotSettings, and
TrustCubit tiers/membership. Resolves the WoT-parameters decision
(open-decisions §B). Trust net stays empty/undetermined until seeded — by
design; users bootstrap their own roots.

apps/app_seeds/lib/i18n/strings_en.g.dart

@@ -76,6 +76,7 @@ class Translations with BaseTranslations<AppLocale, Translations> {
 	late final Translations$chatList$en chatList = Translations$chatList$en.internal(_root);
 	late final Translations$chat$en chat = Translations$chat$en.internal(_root);
 	late final Translations$trust$en trust = Translations$trust$en.internal(_root);
+	late final Translations$wot$en wot = Translations$wot$en.internal(_root);
 }
 
 // Path: app
@@ -1423,6 +1424,75 @@ class Translations$trust$en {
 
 	/// en: 'In your circle'
 	String get circle => 'In your circle';
+
+	/// en: 'Trusted member of the network'
+	String get member => 'Trusted member of the network';
+}
+
+// Path: wot
+class Translations$wot$en {
+	Translations$wot$en.internal(this._root);
+
+	final Translations _root; // ignore: unused_field
+
+	// Translations
+
+	/// en: 'Network of trust'
+	String get title => 'Network of trust';
+
+	/// en: 'Network of trust'
+	String get open => 'Network of trust';
+
+	/// en: 'How trusted membership is decided: people vouch for each other, and trust spreads outward from a set of founding roots.'
+	String get help => 'How trusted membership is decided: people vouch for each other, and trust spreads outward from a set of founding roots.';
+
+	/// en: 'Trust roots'
+	String get roots => 'Trust roots';
+
+	/// en: 'The founding identities the network is anchored to. Add people you trust (paste their identity code); membership is measured outward from them.'
+	String get rootsHelp => 'The founding identities the network is anchored to. Add people you trust (paste their identity code); membership is measured outward from them.';
+
+	/// en: 'No trust roots yet — membership can't be worked out until the network is seeded.'
+	String get noRoots => 'No trust roots yet — membership can\'t be worked out until the network is seeded.';
+
+	/// en: 'Add a trust root'
+	String get addRoot => 'Add a trust root';
+
+	/// en: 'Paste an identity code (npub…)'
+	String get rootHint => 'Paste an identity code (npub…)';
+
+	/// en: 'Add'
+	String get add => 'Add';
+
+	/// en: 'Trust root added'
+	String get rootAdded => 'Trust root added';
+
+	/// en: 'That's not a valid identity code'
+	String get rootInvalid => 'That\'s not a valid identity code';
+
+	/// en: 'Remove'
+	String get remove => 'Remove';
+
+	/// en: 'Advanced parameters'
+	String get params => 'Advanced parameters';
+
+	/// en: 'Duniter rules. Loosen them for a young network; tighten as it grows.'
+	String get paramsHelp => 'Duniter rules. Loosen them for a young network; tighten as it grows.';
+
+	/// en: 'Vouches to become a member'
+	String get sigQty => 'Vouches to become a member';
+
+	/// en: 'Max distance from a root'
+	String get stepMax => 'Max distance from a root';
+
+	/// en: 'Vouch validity (days)'
+	String get validityDays => 'Vouch validity (days)';
+
+	/// en: 'Reset to Duniter defaults'
+	String get reset => 'Reset to Duniter defaults';
+
+	/// en: 'Saved'
+	String get saved => 'Saved';
 }
 
 // Path: intro.slides
@@ -2279,6 +2349,26 @@ extension on Translations {
 			'trust.vouch' => 'I know this person',
 			'trust.vouched' => 'You vouch for them',
 			'trust.circle' => 'In your circle',
+			'trust.member' => 'Trusted member of the network',
+			'wot.title' => 'Network of trust',
+			'wot.open' => 'Network of trust',
+			'wot.help' => 'How trusted membership is decided: people vouch for each other, and trust spreads outward from a set of founding roots.',
+			'wot.roots' => 'Trust roots',
+			'wot.rootsHelp' => 'The founding identities the network is anchored to. Add people you trust (paste their identity code); membership is measured outward from them.',
+			'wot.noRoots' => 'No trust roots yet — membership can\'t be worked out until the network is seeded.',
+			'wot.addRoot' => 'Add a trust root',
+			'wot.rootHint' => 'Paste an identity code (npub…)',
+			'wot.add' => 'Add',
+			'wot.rootAdded' => 'Trust root added',
+			'wot.rootInvalid' => 'That\'s not a valid identity code',
+			'wot.remove' => 'Remove',
+			'wot.params' => 'Advanced parameters',
+			'wot.paramsHelp' => 'Duniter rules. Loosen them for a young network; tighten as it grows.',
+			'wot.sigQty' => 'Vouches to become a member',
+			'wot.stepMax' => 'Max distance from a root',
+			'wot.validityDays' => 'Vouch validity (days)',
+			'wot.reset' => 'Reset to Duniter defaults',
+			'wot.saved' => 'Saved',
 			_ => null,
 		};
 	}