Add configurable output DPI setting (port of upstream PR #379)

Adds output_dpi field to Options (default 96.0) and passes it to the
GraphViz graph attributes. Higher DPI produces sharper PNG/PDF renders,
useful for print-quality harness documentation.

src/wireviz/templates/README.md

@@ -40,6 +40,7 @@ Note that there must be one single space between `--` and `%` at both ends.
 | `<!-- %sheet_total% -->`   | `1` (multi-page documents not yet supported) |
 | `<!-- %diagram% -->`       | Embedded SVG diagram as valid HTML |
 | `<!-- %diagram_png_b64% -->` | Embedded base64 encoded PNG diagram as URI |
+| `<!-- %revision% -->`        | The name of the last revision |
 | `<!-- %{item}% -->`             | String or numeric value of `metadata.{item}` |
 | `<!-- %{item}_{i}% -->`         | Category number `{i}` within dict value of `metadata.{item}` |
 | `<!-- %{item}_{i}_{key}% -->`   | Value of `metadata.{item}.{category}.{key}` |

src/wireviz/wv_dataclasses.py

@@ -87,6 +87,7 @@ class Options:
     color_output_mode: ColorOutputMode = ColorOutputMode.EN_UPPER
     mini_bom_mode: bool = True
     template_separator: str = "."
+    output_dpi: Optional[float] = 96.0
     _pad: int = 0
     # TODO: resolve template and image paths during rendering, not during YAML parsing
     _template_paths: List = field(default_factory=list)

src/wireviz/wv_graphviz.py

@@ -632,6 +632,7 @@ def set_dot_basics(dot, options):
         bgcolor=options.bgcolor.html,
         nodesep="0.33",
         fontname=options.fontname,
+        dpi=f"{options.output_dpi}",
     )  # TODO: Add graph attribute: charset="utf-8",
     dot.attr(
         "node",

src/wireviz/wv_output.py

@@ -15,7 +15,7 @@ from wireviz.wv_utils import (
     smart_file_resolve,
 )
 
-mime_subtype_replacements = {"jpg": "jpeg", "tif": "tiff"}
+mime_subtype_replacements = {"jpg": "jpeg", "svg": "svg+xml", "tif": "tiff"}
 
 
 # TODO: Share cache and code between data_URI_base64() and embed_svg_images()
@@ -64,6 +64,12 @@ def get_mime_subtype(filename: Union[str, Path]) -> str:
     return mime_subtype
 
 
+def _get_latest_revision(metadata: Dict) -> str:
+    if "revisions" not in metadata:
+        return ""
+    return list(metadata.get("revisions"))[-1]
+
+
 def embed_svg_images_file(
     filename_in: Union[str, Path], overwrite: bool = True
 ) -> None:
@@ -152,6 +158,7 @@ def generate_html_output(
         "<!-- %template_sheetsize% -->": metadata.get("template", {}).get(
             "sheetsize", ""
         ),
+        "<!-- %revision% -->": _get_latest_revision(metadata),
     }
 
     def replacement_if_used(key: str, func: Callable[[], str]) -> None: