refactor(core)!: rename Provider to LLMProvider and update implementations

- Export `LLMProvider` from `owlen-core` and replace public `Provider` re-exports.
- Convert `OllamaProvider` to implement the new `LLMProvider` trait with associated future types.
- Adjust imports and trait bounds in `remote_client.rs` to use the updated types.
- Add comprehensive provider interface tests (`provider_interface.rs`) verifying router routing and provider registry model listing with `MockProvider`.
- Align dependency versions across workspace crates by switching to workspace-managed versions.
- Extend CI (`.woodpecker.yml`) with a dedicated test step and generate coverage reports.
- Update architecture documentation to reflect the new provider abstraction.

crates/owlen-core/Cargo.toml

@@ -10,7 +10,7 @@ description = "Core traits and types for OWLEN LLM client"
 
 [dependencies]
 anyhow = { workspace = true }
-log = "0.4.20"
+log = { workspace = true }
 regex = { workspace = true }
 serde = { workspace = true }
 serde_json = { workspace = true }
@@ -24,7 +24,7 @@ futures = { workspace = true }
 async-trait = { workspace = true }
 toml = { workspace = true }
 shellexpand = { workspace = true }
-dirs = "5.0"
+dirs = { workspace = true }
 ratatui = { workspace = true }
 tempfile = { workspace = true }
 jsonschema = { workspace = true }
@@ -42,7 +42,7 @@ duckduckgo = "0.2.0"
 reqwest = { workspace = true, features = ["default"] }
 reqwest_011 = { version = "0.11", package = "reqwest" }
 path-clean = "1.0"
-tokio-stream = "0.1"
+tokio-stream = { workspace = true }
 tokio-tungstenite = "0.21"
 tungstenite = "0.21"