Readme files are always rendered in Markdown format

[LindsayZhou]

Describe the bug
Regardless the actual format, readme files are always rendered in Markdown format.
Included in the service's About tab and the repository's readme page

To Reproduce
Create a repository and commit a readme file.

Expected behavior
For non-Markdown readme files, represent them as normal files.

I personally like to use orgmode files as readme files.
If the service cannot parse the orgmode file, then I export it as a plain text file (emacs built-in feature).

Screenshots
Current:

What I want:

Environment (please complete the following information):

• OS: Alpine Linux 3.19.0
• Terminal: foot
• Version: 0.7.4

Additional context
Here is my rough patch:

diff --git a/pkg/ui/pages/repo/readme.go b/pkg/ui/pages/repo/readme.go
index e977bb9..1b12560 100644
--- a/pkg/ui/pages/repo/readme.go
+++ b/pkg/ui/pages/repo/readme.go
@@ -3,6 +3,7 @@ package repo
 import (
 	"fmt"
 	"path/filepath"
+	"strings"
 
 	"github.com/charmbracelet/bubbles/key"
 	"github.com/charmbracelet/bubbles/spinner"
@@ -34,7 +35,6 @@ type Readme struct {
 func NewReadme(common common.Common) *Readme {
 	readme := code.New(common, "", "")
 	readme.NoContentStyle = readme.NoContentStyle.Copy().SetString("No readme found.")
-	readme.UseGlamour = true
 	s := spinner.New(spinner.WithSpinner(spinner.Dot),
 		spinner.WithStyle(common.Styles.Spinner))
 	return &Readme{
@@ -114,6 +114,13 @@ func (r *Readme) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	case ReadmeMsg:
 		r.isLoading = false
 		r.readmePath = msg.Path
+		readmeExt := strings.ToLower(filepath.Ext(msg.Path))
+		r.code.UseGlamour = (readmeExt == ".md" ||
+			readmeExt == ".markdown" ||
+			readmeExt == ".mdown" ||
+			readmeExt == "mkdn" ||
+			readmeExt == "mdwn" ||
+			readmeExt == "mkd")
 		r.code.GotoTop()
 		cmds = append(cmds, r.code.SetContent(msg.Content, msg.Path))
 	case spinner.TickMsg:
diff --git a/pkg/ui/pages/selection/selection.go b/pkg/ui/pages/selection/selection.go
index 4b9b72a..9f0d884 100644
--- a/pkg/ui/pages/selection/selection.go
+++ b/pkg/ui/pages/selection/selection.go
@@ -2,7 +2,9 @@ package selection
 
 import (
 	"fmt"
+	"path/filepath"
 	"sort"
+	"strings"
 
 	"github.com/charmbracelet/bubbles/key"
 	"github.com/charmbracelet/bubbles/list"
@@ -62,7 +64,6 @@ func New(c common.Common) *Selection {
 		tabs:       t,
 	}
 	readme := code.New(c, "", "")
-	readme.UseGlamour = true
 	readme.NoContentStyle = c.Styles.NoContent.Copy().
 		SetString(defaultNoContent)
 	selector := selector.New(c,
@@ -206,6 +207,13 @@ func (s *Selection) Init() tea.Cmd {
 			if err != nil {
 				continue
 			}
+			readmeExt := strings.ToLower(filepath.Ext(path))
+			s.readme.UseGlamour = (readmeExt == ".md" ||
+				readmeExt == ".markdown" ||
+				readmeExt == ".mdown" ||
+				readmeExt == "mkdn" ||
+				readmeExt == "mdwn" ||
+				readmeExt == "mkd")
 
 			readmeCmd = s.readme.SetContent(readme, path)
 		}