CRITICAL USER DECEPTION: README promises false compilation simplicity

[krystophny]

Users following README compilation examples encounter cryptic build failures due to missing compilation instructions.

BRUTAL USER IMPACT:

• README shows simple 'use fortplot' examples but provides NO compilation guidance
• Users must guess complex module paths: build/gfortran_1FD0EBF408CEEB1F vs build/gfortran_27353C317BE38399/fortplot
• Compilation requires manual discovery of library paths through trial and error
• New users abandon library due to impossible initial setup experience

EVIDENCE:

• 'gfortran -o test test.f90 -I build -L build -lfortplot' fails with "Cannot find -lfortplot"
• Actual working command requires: 'gfortran -o test test.f90 -I build/gfortran_1FD0EBF408CEEB1F -L build/gfortran_27353C317BE38399/fortplot -lfortplot'
• README provides ZERO guidance on discovering these cryptic hash-based paths

BROKEN USER WORKFLOW:

1. User reads README simple examples
2. User attempts to compile following standard pattern
3. User encounters cryptic "Cannot find module/library" errors
4. User abandons library due to impossible setup

SOLUTION REQUIRED:
Add explicit compilation section with working commands and path discovery guidance

[krystophny]

Consolidated into Sprint #2 Issue #978 - README accuracy restoration