refactor(simulation): remove v0.1 content loading system (#655)

Delete the hand-authored YAML content pipeline (server/src/content/) superseded
by the v0.2 generator-first approach (D-122, D-128). Runtime ECS types that were
co-located with content loading have been extracted to dedicated simulation modules:

- simulation/triangle.rs: TriangleState, TriangleCrisisEventQueue, tick/resolve systems
- simulation/line_pool.rs: LinePoolIndex, AccessTier, TrustTier, Mood, LinePoolIndexResource
- simulation/knowledge_grant.rs: KnowledgeGrant, Prerequisites

Monologue systems (trigger_monologue, trigger_recognition_monologue,
trigger_event_monologue) now use hardcoded fallback lines only; the
ContentStoreResource branch and select_pool_line function are removed.

Deleted: content/{loader,types,line_pool,hot_reload,spawn,instantiation,entanglement,mod}.rs
Deleted: tests/{content_loading,content_runtime,content_scaling,template_instantiation,template_schema}.rs
Deleted: bin/line_preview.rs (v0.1 tool)

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

server/src/simulation/dialogue.rs

@@ -23,11 +23,11 @@ use rand::Rng;
 use crate::bridge::types::{DialogueResponseEvent, MonologueEvent, RelationshipState};
 use crate::simulation::conversation::{display_label_for_role, NpcColorIndex, NpcName};
 use crate::storyteller::EngagementRecord;
-use crate::content::line_pool::{
+use crate::simulation::line_pool::{
     AccessTier, IndexedDialogueLine, Mood, Situation, Topic, TrustTier,
 };
-use crate::content::types::KnowledgeGrant;
-use crate::content::LinePoolIndexResource;
+use crate::simulation::knowledge_grant::KnowledgeGrant;
+use crate::simulation::line_pool::LinePoolIndexResource;
 use crate::knowledge::content_registry::ContentEntityRegistry;
 use crate::knowledge::events::{ProcessedEntityGrant, ProcessedFactGrant, ProcessedKnowledgeGrant};
 use crate::knowledge::types::{FactId, KnowledgeConfidence, KnowledgeSource, StableId};
@@ -356,7 +356,7 @@ pub fn select_dialogue_line<'a>(
 /// avoid duplicating the L1-L4 query + scoring logic. Callers handle the
 /// result differently (initial Talk sets ActiveDialogue; follow-up may clear it).
 fn run_dialogue_pipeline<'a>(
-    line_pool: &'a crate::content::line_pool::LinePoolIndex,
+    line_pool: &'a crate::simulation::line_pool::LinePoolIndex,
     location: &str,
     role: &str,
     relationship: RelationshipState,
@@ -1110,11 +1110,11 @@ pub fn process_dialogue_response(
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::content::line_pool::{
+    use crate::simulation::line_pool::{
         AccessTier, IndexedDialogueLine, IndexedDialoguePool, LinePoolIndex, Mood, Situation,
         Topic, TrustTier,
     };
-    use crate::content::LinePoolIndexResource;
+    use crate::simulation::line_pool::LinePoolIndexResource;
     use crate::knowledge::graph::KnowledgeGraph;
     use crate::knowledge::registry::EntityRegistry;
     use crate::npc::Npc;