ar: refresh page (#9567)

* Refresh descriptions:
- add mnemonics
- use `specific` term

* Fix broken placeholders: wrong format

* Replace `.o` with `.ext`

* Don't use leading dashes

* Apply suggestions from code review

pages/common/ar.md

@@ -1,24 +1,25 @@
 # ar
 
-> Create, modify, and extract from archives (`.a`, `.so`, `.o`).
+> Create, modify, and extract from Unix archives. Typically used for static libraries (`.a`) and Debian packages (`.deb`).
+> See also: `tar`.
 > More information: <https://manned.org/ar>.
 
-- Extract all members from an archive:
+- E[x]tract all members from an archive:
 
-`ar -x {{path/to/file.a}}`
+`ar x {{path/to/file.a}}`
 
-- List the members of an archive:
+- Lis[t] contents in a specific archive:
 
-`ar -t {{path/to/file.a}}`
+`ar t {{path/to/file.ar}}`
 
-- Replace or add files to an archive:
+- [r]eplace or add specific files to an archive:
 
-`ar -r {{path/to/file.a}} {{path/to/file1.o}} {{path/to/file2.o}}`
+`ar r {{path/to/file.deb}} {{path/to/debian-binary path/to/control.tar.gz path/to/data.tar.xz ...}}`
 
-- Insert an object file index (equivalent to using `ranlib`):
+- In[s]ert an object file index (equivalent to using `ranlib`):
 
-`ar -s {{path/to/file.a}}`
+`ar s {{path/to/file.a}}`
 
-- Create an archive with files and an accompanying object file index:
+- Create an archive with specific files and an accompanying object file index:
 
-`ar -rs {{path/to/file.a}} {{path/to/file1.o}} {{path/to/file2.o}}`
+`ar rs {{path/to/file.a}} {{path/to/file1.o path/to/file2.o ...}}`