refactor(workflows): hide internal modules from public API

Make 7 modules pub(crate) (condition, graph, lifecycle, node_handler,
run_dir) and 4 modules #[doc(hidden)] (artifact, test_support,
transforms, stylesheet) to reduce the public surface of fabro-workflows.
Internal crate::transform alias replaced with crate::transforms.
External consumers still access what they need via narrowed re-exports.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

lib/crates/fabro-workflows/src/condition.rs

@@ -2,7 +2,6 @@
 ///
 /// The parser lives in `fabro_graphviz::condition`; this module re-exports
 /// `parse_condition` and provides runtime evaluation against `Outcome`/`Context`.
-pub use fabro_graphviz::condition::parse_condition;
 use fabro_graphviz::condition::{Clause, ConditionExpr, Op};
 
 use crate::context::keys;

lib/crates/fabro-workflows/src/lib.rs

@@ -88,35 +88,46 @@ pub fn build_completed_stages(
     stages
 }
 
+#[doc(hidden)]
 pub mod artifact;
 pub mod asset_snapshot;
 pub mod assets;
-pub mod condition;
+pub(crate) mod condition;
 pub mod context;
 pub mod devcontainer_bridge;
 pub mod error;
 pub mod event;
 pub mod git;
-pub mod graph;
+pub(crate) mod graph;
 pub mod handler;
 mod hook_context;
-pub mod lifecycle;
-pub mod node_handler;
+#[allow(dead_code)]
+pub(crate) mod lifecycle;
+pub(crate) mod node_handler;
 pub mod operations;
 pub mod outcome;
 pub mod pipeline;
 pub mod pull_request;
 pub mod records;
 mod retry;
-pub mod run_dir;
+pub(crate) mod run_dir;
 pub mod run_lookup;
 pub mod run_settings;
 pub mod run_status;
 pub mod sandbox_git;
 #[doc(hidden)]
 pub mod test_support;
+#[doc(hidden)]
 pub mod transforms;
 
-pub use transforms as transform;
+// Re-export aliases (back-compat with `fabro_workflows::transform::*` imports)
+#[doc(hidden)]
+pub mod transform {
+    pub use crate::transforms::*;
+}
+#[doc(hidden)]
+pub mod vars {
+    pub use crate::transforms::variable_expansion::*;
+}
+#[doc(hidden)]
 pub use transforms::stylesheet;
-pub use transforms::variable_expansion as vars;

lib/crates/fabro-workflows/src/operations/create.rs

@@ -4,7 +4,7 @@ use fabro_graphviz::graph::Graph;
 
 use crate::error::FabroError;
 use crate::pipeline::{self, TransformOptions, Validated};
-use crate::transform::Transform;
+use crate::transforms::Transform;
 
 #[derive(Default)]
 pub struct CreateOptions {

lib/crates/fabro-workflows/src/pipeline/transform.rs

@@ -1,4 +1,4 @@
-use crate::transform::{
+use crate::transforms::{
     FileInliningTransform, ModelResolutionTransform, StylesheetApplicationTransform, Transform,
     VariableExpansionTransform,
 };

lib/crates/fabro-workflows/src/pipeline/types.rs

@@ -258,7 +258,7 @@ pub struct Finalized {
 /// Options for the TRANSFORM phase.
 pub struct TransformOptions {
     pub base_dir: Option<PathBuf>,
-    pub custom_transforms: Vec<Box<dyn crate::transform::Transform>>,
+    pub custom_transforms: Vec<Box<dyn crate::transforms::Transform>>,
 }
 
 /// Options for the RETRO phase.

lib/crates/fabro-workflows/src/transforms/stylesheet.rs

@@ -1,5 +1,5 @@
 use fabro_graphviz::graph::{AttrValue, Graph};
-pub use fabro_graphviz::stylesheet::{parse_stylesheet, Declaration, Rule, Selector, Stylesheet};
+pub use fabro_graphviz::stylesheet::{parse_stylesheet, Rule, Selector, Stylesheet};
 
 /// Recognized stylesheet properties.
 const STYLESHEET_PROPERTIES: &[&str] =