feat(i18n): add internationalization with DE, FR, ES, PT translations (#12)

Add a compile-time i18n system with 270 translation keys across 5 locales
(EN, DE, FR, ES, PT). Translations are embedded via include_str! and parsed
lazily into flat HashMaps with English fallback for missing keys.

- Add src/i18n module with Locale enum, t()/tw() lookup functions, and tests
- Add JSON translation files for all 5 locales under assets/i18n/
- Provide locale Signal via Dioxus context in App, persisted to localStorage
- Replace all hardcoded UI strings across 33 component/page files
- Add compact locale picker (globe icon + ISO alpha-2 code) in sidebar header
- Add click-outside backdrop dismissal for locale dropdown

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Co-authored-by: Sharang Parnerkar <parnerkarsharang@gmail.com>
Reviewed-on: #12

src/pages/organization/pricing.rs

@@ -2,6 +2,7 @@ use dioxus::prelude::*;
 
 use crate::app::Route;
 use crate::components::{PageHeader, PricingCard};
+use crate::i18n::{t, tw, Locale};
 use crate::models::PricingPlan;
 
 /// Organization pricing page displaying three plan tiers.
@@ -10,14 +11,17 @@ use crate::models::PricingPlan;
 /// organization dashboard.
 #[component]
 pub fn OrgPricingPage() -> Element {
+    let locale = use_context::<Signal<Locale>>();
+    let l = *locale.read();
+
     let navigator = use_navigator();
-    let plans = mock_plans();
+    let plans = mock_plans(l);
 
     rsx! {
         section { class: "pricing-page",
             PageHeader {
-                title: "Pricing".to_string(),
-                subtitle: "Choose the plan that fits your organization".to_string(),
+                title: t(l, "org.pricing_title"),
+                subtitle: t(l, "org.pricing_subtitle"),
             }
             div { class: "pricing-grid",
                 for plan in plans {
@@ -34,52 +38,56 @@ pub fn OrgPricingPage() -> Element {
     }
 }
 
-/// Returns mock pricing plans.
-fn mock_plans() -> Vec<PricingPlan> {
+/// Returns mock pricing plans with translated names and features.
+///
+/// # Arguments
+///
+/// * `l` - The active locale for translating user-facing plan text
+fn mock_plans(l: Locale) -> Vec<PricingPlan> {
     vec![
         PricingPlan {
             id: "starter".into(),
-            name: "Starter".into(),
+            name: t(l, "pricing.starter"),
             price_eur: 49,
             features: vec![
-                "Up to 5 users".into(),
-                "1 LLM provider".into(),
-                "100K tokens/month".into(),
-                "Community support".into(),
-                "Basic analytics".into(),
+                tw(l, "pricing.up_to_users", &[("n", "5")]),
+                t(l, "pricing.llm_provider_1"),
+                t(l, "pricing.tokens_100k"),
+                t(l, "pricing.community_support"),
+                t(l, "pricing.basic_analytics"),
             ],
             highlighted: false,
             max_seats: Some(5),
         },
         PricingPlan {
             id: "team".into(),
-            name: "Team".into(),
+            name: t(l, "pricing.team"),
             price_eur: 199,
             features: vec![
-                "Up to 25 users".into(),
-                "All LLM providers".into(),
-                "1M tokens/month".into(),
-                "Priority support".into(),
-                "Advanced analytics".into(),
-                "Custom MCP tools".into(),
-                "SSO integration".into(),
+                tw(l, "pricing.up_to_users", &[("n", "25")]),
+                t(l, "pricing.all_providers"),
+                t(l, "pricing.tokens_1m"),
+                t(l, "pricing.priority_support"),
+                t(l, "pricing.advanced_analytics"),
+                t(l, "pricing.custom_mcp"),
+                t(l, "pricing.sso"),
             ],
             highlighted: true,
             max_seats: Some(25),
         },
         PricingPlan {
             id: "enterprise".into(),
-            name: "Enterprise".into(),
+            name: t(l, "pricing.enterprise"),
             price_eur: 499,
             features: vec![
-                "Unlimited users".into(),
-                "All LLM providers".into(),
-                "Unlimited tokens".into(),
-                "Dedicated support".into(),
-                "Full observability".into(),
-                "Custom integrations".into(),
-                "SLA guarantee".into(),
-                "On-premise deployment".into(),
+                t(l, "pricing.unlimited_users"),
+                t(l, "pricing.all_providers"),
+                t(l, "pricing.unlimited_tokens"),
+                t(l, "pricing.dedicated_support"),
+                t(l, "pricing.full_observability"),
+                t(l, "pricing.custom_integrations"),
+                t(l, "pricing.sla"),
+                t(l, "pricing.on_premise"),
             ],
             highlighted: false,
             max_seats: None,