Migrate jinja to minijinja2 (#2025)

The `jinja` and `jinja-runtime` crates were migrated to use MiniJinja
2.x, addressing API changes and rendering differences.

Key changes include:

* **Dependency Update**: MiniJinja was upgraded from 1.0.16 to 2.10.2 in
`engine/Cargo.toml` and `engine/baml-lib/jinja/Cargo.toml`, with the
"serde" feature added to resolve deprecation warnings.
*   **Object Trait Migration**:
* `StructObject` was replaced with the new `Object` trait across
`baml_value_to_jinja_value.rs`, `render_context.rs`, and `minijinja.rs`.
    *   The `call` method signature was updated to `self: 
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----

> [!IMPORTANT]
> Migrate from MiniJinja 1.x to 2.x, updating dependencies and adapting
to API changes, including replacing `StructObject` with `Object` trait
and updating method signatures.
> 
>   - **Dependency Update**:
>     - Upgrade `minijinja` from 1.0.16 to 2.10.2 in `Cargo.toml` files.
> - Add `serde` feature to `minijinja` to resolve deprecation warnings.
>   - **Object Trait Migration**:
> - Replace `StructObject` with `Object` trait in `minijinja.rs`,
`baml_value_to_jinja_value.rs`, and `render_context.rs`.
>     - Update `call` method signatures to use `self: &Arc<Self>`.
> - Implement `render` method for `Object` trait in `minijinja.rs`,
`baml_value_to_jinja_value.rs`, and `output_format/mod.rs`.
>   - **Code Adjustments**:
>     - Handle `CallArg` variants in `expr.rs` and `pretty_print.rs`.
> - Update `parse_as_function_call` and `tracker_visit_expr` to handle
new `minijinja` AST structures.
> - Modify `evaluate_type` tests to align with new syntax in
`test_stmt.rs`.
> 
> <sup>This description was created by </sup>[<img alt="Ellipsis"
src="https://img.shields.io/badge/Ellipsis-blue?color=175173">](https://www.ellipsis.dev?ref=BoundaryML%2Fbaml&utm_source=github&utm_medium=referral)<sup>
for 0c832f2. You can
[customize](https://app.ellipsis.dev/BoundaryML/settings/summaries) this
summary. It will automatically update as commits are pushed.</sup>

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---------

Co-authored-by: Cursor Agent <cursoragent@cursor.com>

Author: aaronvg

engine/Cargo.lock

@@ -74,7 +74,7 @@ baml-lsp-types = { path = "baml-lsp-types" }
 jsonish = { path = "baml-lib/jsonish" }
 log = "0.4.20"
 # TODO: disable imports, etc
-minijinja = { version = "1.0.16", default-features = false, features = [
+minijinja = { version = "2.10.2", default-features = false, features = [
   "macros",
   "builtins",
   "debug",
@@ -87,6 +87,7 @@ minijinja = { version = "1.0.16", default-features = false, features = [
   "custom_syntax",
   "internal_debug",
   "deserialization",
+  "serde",
   # We don't want to use these features:
   # multi_template
   # loader

engine/Cargo.toml

@@ -1,5 +1,6 @@
 use crate::{BamlMedia, BamlValue};
 use std::fmt;
+use std::sync::Arc;
 
 /// A wrapper around a jinja expression. The inner `String` should not contain
 /// the interpolation brackets `{{ }}`; it should be a bare expression like
@@ -77,7 +78,7 @@ impl std::fmt::Debug for MinijinjaBamlMedia {
 
 impl minijinja::value::Object for MinijinjaBamlMedia {
     fn call(
-        &self,
+        self: &Arc<Self>,
         _state: &minijinja::State<'_, '_>,
         args: &[minijinja::value::Value],
     ) -> Result<minijinja::value::Value, minijinja::Error> {
@@ -86,4 +87,8 @@ impl minijinja::value::Object for MinijinjaBamlMedia {
             format!("BamlImage has no callable attribute '{args:#?}'"),
         ))
     }
+
+    fn render(self: &Arc<Self>, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self, f)
+    }
 }